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To identify optimal monolayers for photocatalytic water splitting, we screened the lowest-energy structures of CdAl 2 Se 4 and HgAl 2 Se 4 monolayers with the P -3m1 space group from two pools of 675 allotropes. Unfortunately, the valence band maximum of these newfound monolayers did not meet the potential requirement for the oxygen evolution reaction. This led us to explore AAl 2 Se 4 /XSe 2 (A = Cd, Hg; X = Ti, Zr, Hf) heterostructures. Among these, we constructed several Z-schemes for overall water splitting, achieving a maximum solar-to-hydrogen efficiency (η ′ STH) of 38.28%. Non-adiabatic molecular dynamics simulations revealed that the electron transfer for hydrogen evolution reaction (HER) and hole transfer for oxygen evolution reaction (OER) in HgAl 2 Se 4 /ZrSe 2 and CdAl 2 Se 4 /HfSe 2 heterostructures are slower compared to the other five heterostructures, suggesting that their reduction and oxidation activities are well-protected. Notably, CdAl 2 Se 4 /TiSe 2 demonstrated the shortest electron-hole recombination time, indicating superior photocatalytic efficiency for the Z-scheme. Additionally, the Gibbs free energies for HERs and OERs in CdAl 2 Se 4 /TiSe 2 , CdAl 2 Se 4 /ZrSe 2 , and CdAl 2 Se 4 /HfSe 2 are lower than the energies provided by the overpotential, implying spontaneous HER and OER processes. Therefore, AAl 2 Se 4 /XSe 2 (A = Cd, Hg; X = Ti, Zr, Hf) heterostructures, particularly CdAl 2 Se 4 /TiSe 2 , show great promise as candidates for efficient photocatalytic water splitting to produce hydrogen. [Display omitted] • The stable structures of AAl 2 Se 4 (A = Cd, Hg) monolayers are screened. • The highest STH efficiency of the HgAl 2 Se 4 /TiSe 2 heterostructure can reach 38.28%. • Photocatalytic HER/OER with CdAl 2 Se 4 /XSe 2 heterostructures spontaneously proceed. • NAMD simulations reveal that CdAl 2 Se 4 /TiSe 2 has favorable carrier migrations. • CdAl 2 Se 4 /TiSe 2 heterostructure is the most optimal based on all evaluated criteria. [ABSTRACT FROM AUTHOR]

g-C 3 N 4 is a promising metal-free photocatalyst for hydrogen production, whose application is difficult due to the low mobility of charge carriers and rapid electron-hole recombination. Here we propose a new route to improve its response to simulated sunlight and prevent electron-hole recombination by grafting mixed Ag–NiO (1:1 nominal Ag/NiO weight ratio) materials, as an alternative to platinum group metal co-catalysts. g-C 3 N 4 was prepared by urea pyrolysis, whereas Ag–NiO was prepared by a co-precipitation method, and then the composites were prepared by physical mixing using sonication-grinding. The presence of Ag–NiO on the surface plays a key role in accepting excited electrons and enhancing their lifetime for a subsequent reduction of protons to hydrogen. Hydrogen production was carried out from the photoreforming of ethanol under simulated sunlight. The results revealed that 2% (Ag–NiO)/g-C 3 N 4 is effective among others with 5.2 times higher H 2 production than unmodified g-C 3 N 4. The percentage of ethanol in the ethanol/water ratio is very important as we have found that with increasing its quantity, the evolution of hydrogen becomes significant. • New series of g-C 3 N 4 photocatalysts modified with mixed Ag–NiO. • Innovative synthesis of isolated Ag–NiO and (Ag–NiO)/g-C 3 N 4 composite. • Ag–NiO significantly reduces electron-hole recombination. • The optimal composite is 2% (Ag–NiO)/g-C 3 N 4. • Hydrogen evolution via ethanol photoreforming under simulated sunlight. [ABSTRACT FROM AUTHOR]

The paper presents an investigation on the optoelectronic and photocatalytic properties of titanium-nitride (TiN) thin films, modified through the introduction of metal ions (Au, Ag, and Cu) during implantation, followed by thermal annealing. Employing high-resolution microscopic and spectroscopic techniques, we examined the microstructural and compositional features of the films in detail. The films exhibited a crystalline structure with distinct columnar patterns, attributed to defect release and recovery during annealing. Furthermore, metal nanoparticles were detected in samples implanted with gold and silver ions, indicating coalescence processes, while no such particles were observed in the case of Cu ions. Post-implantation annealing also led to surface oxidation and the formation of anatase TiO 2 , with a coexistence of TiO 2 , TiN, metallic Au and Ag, and CuO phases in subsurface regions. Comparative optical measurements revealed significant changes in photoluminescence efficiency and photocatalytic response of modified TiN. All implanted samples showed reduced photoluminescence intensity compared to pristine titanium-nitride, with the Au-implanted film exhibiting the most significant decrease, due to the presence of surface Au nanoparticles, thus resulting in the slower electron-hole recombination rates and enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

The sustainability and feasibility of using visible irradiation in photocatalysis is a promising approach for water purification. In this study, photocatalytic degradation of a widely used analgesic and antipyretic drug, acetaminophen (ACM), with metal-loaded an efficient photocatalyst (TiO 2 NPs-Co/Polycalix (Christen et al., 2010) [4]resorcinarene (TCP)) was inv estigated using visible light. photocatalyst structural, surface, and morphological features were characterized using FTIR, XRD, TEM, EDX, PL, and DRS analyses. Considering various sites of Polycalix (Christen et al., 2010) [4]resorcinarene in the TCP, studied by trapping experiments. A novel charge transfer bridge for electron-hole recombination is made possible by using Co and TiO 2 as electron transfer mediators with electronic conductivity. This results in efficient process and energy optimization, which makes it easier for ACM to degrade throughout the absorption process. The ACM (15 and 40 mg/L) achieved complete degradation under visible light irradiation with 0.6 g/L of TCP at pH = 5.0 during 120 min reaction because of the good synergetic effect of the catalyst systems. Additionally, the intermediates generated by photo electrocatalytic activities were identified, and two potential paths for degradation were suggested. Some of these organic products were identified by High-Performance Liquid Chromatography (HPLC). [ABSTRACT FROM AUTHOR]

The cadmium manganese sulfide, despite being recognized as a highly efficient photocatalytic semiconductor for hydrogen evolution, faces significant challenges in terms of charge recombination when used solely as a catalyst for photocatalytic hydrogen production. The construction of heterojunction photocatalysts is regarded as one of the effective strategies to enhance the efficiency of photocatalytic hydrogen production. In this work, Zn-doped CdSe was adopted to enhance the photocatalytic active sites of the twinned Mn 0.65 Cd 0.35 S. As results, the photocatalytic hydrogen evolution of Zn–CdSe-1/T-MCS-40 can reach approximately 47447.15 μmol g−1 after 5 h, representing a 15 times increase compared to Mn 0.65 Cd 0.35 S. Besides, the hydrogen evolution rate shows almost no significant attenuation after four consecutive cycles (20 h). The significant achievement can be largely attributed to the successful construction of an S-scheme heterojunction of Zn – CdSe-1/T-MCS-40, which effectively minimized the charge transfer distance and suppressed the recombination of photo-generated electron-hole pairs. Additionally, the incorporation of Zn-doped CdSe significantly expands the response range to visible light, thereby providing a conceptual framework for advancing the design of solar-to-chemical energy conversion and effectively guiding the fabrication of metal sulfide-based photocatalytic heterojunctions. • Zn doping broadens the light absorption range of CdSe. • Zn–CdSe is coupled with T-MCS to form the S-scheme heterojunction. • The photocatalytic rate of Zn–CdSe-1/T-MCS-40 exhibits a 15 enhancement compared to Mn 0.65 Cd 0.35 S. • The separation of photogenerated carrier is accelerated by the construction of S-scheme heterojunction. [ABSTRACT FROM AUTHOR]

Zinc sulfide/molybdenum disulfide (ZnS@MoS 2) nanorods composites were synthesized by straightforward hydrothermal method. Experimental investigations revealed that the kinetic coefficient (k) of ZnS@MoS 2 was 0.0667 min−1 within 30 min, with a degradation efficiency of 88.6 % toward methylene blue dye in presence of both stirring and light. These performances were notably higher compared to conditions with either light or stirring irradiation alone. Moreover, ZnS@MoS 2 composites not only had excellent catalytic activity but also good cyclic stability. The catalytic mechanism of ZnS@MoS 2 for degradation of MB organic pollutant was further discussed based on relevant characterization. Under both stirring and light conditions, the strong piezoelectric field effectively promoted charge carriers separation and reduced the electron-hole recombination rate, thus enhancing catalytic degradation efficiency for ZnS@MoS 2. This research holds significant importance for the development of high-performance catalysts in wastewater treatments field. [Display omitted] • A novel ZnS@MoS 2 nanorods composites catalyst was rationally designed. • ZnS@MoS 2 exhibited superior catalytic activity and stability toward degradation of methylene blue dye. • Excellent catalytic performance was mainly ascribed to the efficient charge carriers separation. • A possible catalytic mechanism of ZnS@MoS 2 was clarified. [ABSTRACT FROM AUTHOR]

This work focuses on the synthesis and characterization of nanoscale nickel oxide (NiO) nanoparticles doped with manganese (Mn) utilizing the cost-effective co-precipitation technique. For extensive characterization, a range of analytical methods are used, such as photoluminescence (PL) spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, ultraviolet–visible (UV) spectroscopy, and Brunauer–Emmett–Teller (BET) surface area analysis. The findings demonstrate that the addition of Mn causes the synthesized nanoparticles' crystalline size to decrease, which narrows the band gap to 3.13 eV. Furthermore, compared to pure NiO (44.11 m2/g), the surface area of Mn-doped NiO increases to 178.87 m2/g. Also as compared to pure NiO the electron-hole recombination rate of % Mn-doped NiO has decreased and an increase in the defect is observed. The study of Mn-doped NiO nanoparticles' photocatalytic activity against Rhodamine B (Rh. B) demonstrates their improved efficiency under solar light irradiation, as evidenced by their degradation up to 97.57 %, which is higher than that of pure NiO (90.94 %) in 70 min. Numerous aspects are investigated, including pH, catalyst dosage, original dye concentration, and scavenger studies. Studies on regeneration show that 5 % Mn-doped NiO nanoparticles may be recycled effectively and steadily for up to five cycles. These results demonstrate how effective photocatalysts for environmental remediation applications may be made from Mn-doped NiO nanoparticles. [ABSTRACT FROM AUTHOR]

The electronic, optical, and photocatalytic features of a newly proposed 2D material-based van der Waals heterobilayer, formed by vertically stacking monolayered SiS and AlN, have been investigated. The feasibility of utilizing this heterojunction as a potential photocatalyst for spontaneous water decomposition has been predicted by using the ab initio calculations. The findings reveal that the SiS@AlN heterobilayer can be stacked in four different patterns, resulting in a direct band gap ranging from 2.11 to 2.70 eV, as determined by HSE-06 calculations. The SiS@AlN composites exhibit appropriate band-edge locations for the oxidation and reduction reactions of water splitting. Moreover, the photocatalytic activity of SiS@AlN composites is significantly influenced by the electrolyte's pH. At equilibrium, the composite displays a direct Z-scheme band alignment, which facilitates the effective spatial separation of photo-excited charges and extends their lifetimes. Additionally, a significant built-in electric field is generated at the composite interface, further preventing the recombination of photo-excited electron-hole pairs. Furthermore, the hetero-bilayers exhibit better absorption of sunlight in both the visible and ultraviolet regions compared to individual 2D-SiS and 2D-AlN. These findings highlight the potential of the SiS@AlN hetero-bilayer for applications in solar water decomposition and optical device technologies. [Display omitted] • The SiS@AlN vdW heterostructures possess a direct bandgaps. • The SiS@AlN heterojunction equipped with direct Z-scheme type. • Exhibiting outstanding optical absorption ability in the visible and UV regions. • The SiS@AlN vdW heterostructures show overall water-splitting capability. • The photocatalytic performance of SiS@AlN heterobilayer is affected by the pH of water. [ABSTRACT FROM AUTHOR]

In this research, we present a novel facile, scalable, and template-free technique of synthesizing graphitic carbon nitride (g-C 3 N 4) nanotubes for generating hydrogen through photocatalysis. The hybrid technique involves a two-fold mixing of the precursor materials melamine (M) and cyanuric acid (CA), involving ball milling followed by solution mixing. By varying the M:CA molar ratios, different compositions of g-C 3 N 4 nanotubes were fabricated. The study focused on examining the surface characteristics and the photocatalytic hydrogen evolution performance of these nanotubes. Nanotubes with high specific surface area of 206 m2 g−1 for M:CA molar ratio of 1:3 and 178 m2 g−1 for M:CA molar ratio of 1:5 were produced, with H 2 evolution rates of 543 μmol h−1 g−1 and 740 μmol h−1 g−1 respectively, which were an increase of 4 and 5-fold, respectively, in comparison to the pristine sample. The enhanced efficiency of hydrogen production through photocatalysis by nanotubes, when contrasted with pristine material, can be ascribed to their high crystallinity, superior specific surface areas, decreased recombination rates of electron-hole pairs generated during light exposure, and improved dynamics of charge carriers. This hybrid technique provides a new pathway for cost-effective fabrication of g-C 3 N 4 nanotubes with substantial surface areas and high yield photocatalysts on an industrial scale, without the use of templates and hydrothermal processes for efficient hydrogen generation. [Display omitted] • Graphitic carbon nitride (g-C 3 N 4) nanotubes were synthesized using a novel hybrid synthesis technique involving dual precursor mixing. • High specific surface area g-C 3 N 4 nanotubes of ∼206 m2 g−1 and 178 m2 g−1 were achieved. • A g-C 3 N 4 nanotube with a 1:3 melamine-cyanuric acid molar ratio achieved enhanced H 2 evolution performance (740 µmol h⁻¹ g⁻¹). • The stability of g-C 3 N 4 nanotubes was shown by the consistent H 2 evolution rate during extended irradiation. [ABSTRACT FROM AUTHOR]

CeO 2 is renowned photocatalyst with 2.8 eV band gap energy and exceptional optical features. However, the slow charge transportation and the fast recombination of the electron-hole pair hindered the photocatalytic efficiency. In this pioneering research, S-scheme CuO/CeO 2 heterojunctions were engineered sonochemically with rational compositions of CeO 2 and CuO nanoparticles for enhanced the photocatalytic efficiency of CeO 2 in destructing rhodamine B dye under full solar radiations. Diffuse reflectance spectrum [DRS], photoluminescence [PL], high resolution transmission electron microscope [HRTEM], selected area electron diffraction [SAED], N 2 -adsorption-desorption isotherm, X-ray photoelectron spectroscopy [XPS] and X-ray diffraction [XRD] investigated the physicochemical properties of CuO/CeO 2 heterojunction. Monoclinic CuO nanoparticles of 8 nm size are facilely incorporated in cubic CeO 2 crystallites of 27.3 nm through substitution of Ce4+ by Cu2+ ions which ascribed to smaller ionic radii of Cu2+ compared with Ce4+ and Ce3+ ions. Homogeneous distribution of CuO nanoparticles on CeO 2 surface was further investigated by SEM and TEM analysis. HRTEM, XRD, SAED and XPS analysis recorded the co-existence of crystalline peaks of CeO 2 and CuO implying the successful construction of CuO/CeO 2 heterojunction. The depression in the surface area of CeO 2 from 91.4 to 83.6 m2/g with incorporating 5 wt % of CuO revealed the deposition of CuO on CeO 2 surface. XPS analysis implied the existence of Ce3+ and oxygen vacancies that provide more adsorption sites for oxygen, which are beneficial for enhancing the catalytic performance of catalysts. CuO nanoparticles with 1.3 eV band energy enhanced the visible light absorbability of the heterojunctions in deep visible region for broading the photocatalytic response. Significant reduction in photoluminescence signals intensity by 60 % with incorporation 5 wt % of CuO revealed the favorable reduction in the rate of electron-hole recombination. In particular, CeCu5 containing 5 wt % CuO expelled 96 % of RhB dye within 6-h under solar simulator compared with 13 % removal on pristine CeO 2 and CuO surface. Hot radicals and positive holes degraded RhB dye molecules on the heterojunction surface as elucidated from scavenger experiments and PL analysis of terephthalic acid. The exceptional removal of RhB dye under solar radiation was ascribed to the alignment in the band structure of CeO 2 and CuO nanoparticles and the successful production of an efficient S-scheme heterojunction with strong redox potential and better electron transportation and separation. [ABSTRACT FROM AUTHOR]

This research involved synthesizing In 2 S 3 –In(OH) 3 nanosheets through a simple hydrothermal method at a low reaction temperature. The impact of different indium chloride concentrations on the morphology and crystal structure of In 2 S 3 –In(OH) 3 nanostructures was investigated. The discussion extended to the photocatalytic hydrogen evolution of both In 2 S 3 –In(OH) 3 nanosheets and nanofibers. These findings indicated that In 2 S 3 –In(OH) 3 nanofibers exhibited optimal photocatalytic hydrogen production at various indium chloride concentrations. Furthermore, In 2 S 3 –In(OH) 3 –ZnS heterostructures were created by reacting In 2 S 3 –In(OH) 3 nanosheets with varying concentrations of ZnS precursors. The study delved into the morphology and crystal structure, emphasizing photocatalytic hydrogen production in In 2 S 3 –In(OH) 3 –ZnS nanofibers under different concentrations of ZnS precursors. Remarkably, the In 2 S 3 –In(OH) 3 –ZnS nanofibers demonstrated exceptional hydrogen production efficiency, attributed to their larger specific surface area, improved blue light absorption, and reduced electron-hole pair recombination. Additionally, a comprehensive analysis explored the photocatalytic reaction mechanism, pH values, sacrificial reagents, sacrificial reagent concentrations, light source types, and intensities. These results highlighted the exceptional reusability of In 2 S 3 –In(OH) 3 –ZnS nanofibers in photocatalytic hydrogen production, showcasing their potential for cost-effective and highly efficient applications in diverse fields. [Display omitted] • Synthesized In 2 S 3 –In(OH) 3 nanosheets using a simple hydrothermal method. • Explored photocatalytic hydrogen evolution in nanosheets and nanofibers. • In 2 S 3 –In(OH) 3 –ZnS nanofibers demonstrated exceptional hydrogen production efficiency. • Analyzed photocatalytic reaction mechanism, pH values, sacrificial reagents, and light sources. • Demonstrated high reusability and efficiency potential for various applications. [ABSTRACT FROM AUTHOR]

• Cation-induced chloride intercalation in bismuth oxide via one-pot hydrothermal. • Ta-BiOCl/Bi 24 O 31 Cl 10 shoulder-by-shoulder micro-ribbon architectures. • Semi-coherent interfaces between Ta-BiOCl and Ta-Bi 24 O 31 Cl 10. • Successive type-II/type-II heterojunctions for enhanced photocharge separation. • Highly efficient photodegradation activity under visible light. Developing heterojunction photocatalyst with well-matched interfaces and multiple charge transfer paths is vital to boost carrier separation efficiency for photocatalytic antibiotics removal, but still remains a great challenge. In present work, a new strategy of chloride anion intercalation in Bi 2 O 3 via one-pot hydrothermal process is proposed. The as-prepared Ta-BiOCl/Bi 24 O 31 Cl 10 (TBB) heterojunctions are featured with Ta-Bi 24 O 31 Cl 10 and Ta-BiOCl lined shoulder-by-shouleder via semi-coherent interfaces. In this TBB heterojunctions, the well-matched semi-coherent interfaces and shoulder-by-shoulder structures provide fast electron transfer and multiple transfer paths, respectively, leading to enhanced visible light response and improved photogenerated charge separation. Meanwhile, a type-II heterojunction for photocharge separation has been obtained, in which photogenerated electrons are drove from the CB (conduction band) of Ta-Bi 24 O 31 Cl 10 to the both of bilateral empty CB of Ta-BiOCl and gathered on the CB of Ta-BiOCl, while the photogenerated holes are left on the VB (valence band) of Ta-Bi 24 O 31 Cl 10 , effectively hindering the recombination of photogenerated electron-hole pairs. Furthermore, the separated electrons can effectively activate dissolved oxygen for the generation of reactive oxygen species (·O 2 −). Such TBB heterojunctions exhibit remarkably superior photocatalytic degradation activity for tetracycline hydrochloride (TCH) solution to Bi 2 O 3 , Ta-BiOCl and Ta-Bi 24 O 31 Cl 10. This work not only proposes a Ta-BiOCl/Bi 24 O 31 Cl 10 shoulder-by-shoulder micro-ribbon architectures with semi-coherent interfaces and successive type-II heterojunction for highly efficient photocatalytic activity, but offers a new insight into the design of highly efficient heterojunction through phase-structure synergistic transformation strategy. [Display omitted] [ABSTRACT FROM AUTHOR]

The production of solar hydrogen presents a compelling opportunity to harness solar energy, playing a crucial role in addressing climate change and reducing reliance on fossil fuels. The progress of the hydrogen economy largely depends on establishing hydrogen production as a key foundational element. Moreover, selecting appropriate materials to support the main catalyst is vital for enhancing hydrogen production. This article furnishes a simple, affordable approach to existing water-splitting technologies that harness solar energy as the primary source for hydrogen production. To achieve this, the impact of GO content on ZnO nanoparticles/GO compositions' photoelectrochemical efficiency is studied. While all the presented samples show sensitivity to light, the sample with 0.35% GO performs the best, demonstrating the highest photocurrent density, the lowest rate of electron-hole recombination, and the greatest photoelectrochemical efficiency. • The PEC behavior of ZnO/GO nano composite was studied with varying GO amount. • Efficient separation of e & h decreases recombination and charge transfer resistance. • The 0.35-%G sample shows the most enhanced PEC and best photo stability properties. • The 0.35-%G sample has the narrowest band-gap and the lowest-intensity PL spectrum. • The 0.35%G sample provides the most optimal conditions for water splitting. [ABSTRACT FROM AUTHOR]

The electronic and photocatalytic properties of a type-II ZnS/HfS 2 heterojunction are comprehensively analyzed through first-principles calculations in this paper. By calculating the binding energy and phonon spectrum of five potential stacking patterns, the stable structure of the ZnS/HfS 2 heterojunction is determined. The electronic structure calculations indicate that the heterojunction has a type-II alignment with a 1.26 eV band gap. The heterojunction exhibits high carrier mobilities (4387.36 and 9561.39 cm2V–1S−1 for X and Y directions). The photocatalytic water splitting process of the heterojunction can be explained by the direct Z-scheme mechanism. The built-in electric field enables rapid recombination of electron-hole pairs at CBM and VBM, while the hydrogen evolution reaction and oxygen evolution reaction can separately be achieved at the ZnS layer and HfS 2 layer to complete the overall water splitting. The free energy analysis indicates that the ZnS/HfS 2 heterojunction has high activity for overall water splitting under illumination. Moreover, the calculated solar-to-hydrogen efficiency of the heterojunction reaches 30%, ensuring its photocatalytic performance. Remarkably, the type-II alignment is maintained and the catalytic performance can be further improved under biaxial strain because of the enhanced optical absorption in visible light and the reduced band gap. This work reveals that ZnS/HfS 2 heterojunction is a potentially novel photocatalytic material for efficient overall water splitting. [Display omitted] • Proposed novel type-II ZnS/HfS 2 heterojunction with 1.26 eV band gap. • Achieves overall water splitting via direct Z-scheme mechanism. • High carrier mobility and 30% solar-to-hydrogen efficiency. • Enhanced catalytic performance under biaxial strain. [ABSTRACT FROM AUTHOR]

AlN and ReS 2 monolayers are the foundation for constructing the unique 2D vdW heterojunction. Based on density functional theory, the photocatalytic performance of AlN/ReS 2 heterojunction was systematically studied using first-principles calculation methods. According to the calculation findings, the AlN/ReS 2 heterojunction possesses a band gap of 1.79 eV, and the staggered band structure efficiently divides the holes and electrons produced by photo-generated light. The Z-scheme charge transfer mechanism is achieved via the AlN/ReS 2 heterojunction, allowing the recombination of electron-hole pairs within the heterojunction. In the AlN layer for reduction processes, this mechanism leaves highly reducing photo-generated electrons, whereas in the ReS 2 layer for oxidation reactions, it leaves highly oxidizing photo-generated holes. The AlN/ReS 2 heterojunction's band edge location also spans the pH = 1 to 7 water oxidation-reduction potential. The AlN/ReS 2 heterojunction exhibits good light absorption capabilities and charge carrier mobility. As a result, for applications involving water splitting, the AlN/ReS 2 heterojunction is a promising photocatalyst. • The existence of AlN/ReS 2 vdW heterojunction has been predicted theoretically. • The Z-scheme AlN/ReS 2 heterojunction can separate photogenerated carriers. • The AlN/ReS 2 vdW heterostructure enables photocatalytic water splitting. [ABSTRACT FROM AUTHOR]

For photocatalysis technology to be applied industrially, there has been a significant increase in the need for visible-light-driven photocatalysts that possess exceptional superparamagnetic characteristics to facilitate easy separation. Hence, in this study, rare earth elements (RE) (Sm, Yb, Dy, Er, and Ho) were systematically doped into manganese ferrite (MF) using the coprecipitation method to serve two purposes, namely, reducing the photogenerated electron-hole recombination during photocatalysis and modifying the magnetic properties of MF to become superparamagnetic. The synthesised Re-doped MF was found to be visible light active, as evidenced by the transient photocurrent response and the obtained band gaps, which were in the range of 1.84–1.93 eV. From the cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization plots, it was evident that different RE element dopants have different effects on improving the electrochemical properties of MF. Overall, fast electron transfer of the synthesised materials was found to decrease in the following order: Sm-MF > Dy-MF > Ho-MF > MF > Er-MF > Yb-MF. The g-factor and peak-to-peak line width were found to be in the range of (2.221–2.317) and (93.17–149.85 mT), respectively. The resonance field and hysteresis loop (H c) were found to be in the range of (289.2–301.86 mT) and (8.24–32.61 mT), respectively. Overall, the synthesised RE-doped MF exhibits ferromagnetic properties, and the obtained small H c values hint at these particles exhibiting superparamagnetic properties. In summary, doping MF with Sm, Dy, and Ho is more desirable as it alters the magnetic properties towards superparamagnetic and improves its electrochemical properties. Thus, this study is of importance in advancing the field of photocatalysis in water treatment and material science. • RE (Sm, Dy, Ho, Er, and Yb) were successfully incorporated into the MF spinel structure. • Sm, Dy and Ho dopants improved the electrochemical and optical properties of MF. • The magnetic properties of MF were improved. • The produced photocatalysts were visible light active. [ABSTRACT FROM AUTHOR]

In this study, ZnS/P-doped-MoS 2 (ZnS/P–MoS 2) composite was synthesized for the first time via in-situ precipitation approach, whereby P–MoS 2 flowers were decorated with ZnS nanoparticles. Compared to ZnS, composite has significantly wider range of visible light absorption region, lower recombination rate and large surface area. The photocatalytic activity was demonstrated by ZnS/5%P–MoS 2 (ZPM-2) composite with hydrogen (H 2) generation rate of 1.2306 mmolg−1h−1, 46.12% of benzyl alcohol (BA) to benzaldehyde (BAL) conversion with 98.30% selectivity and 98.52% brilliant green (BG) dye degradation in 40 min. The improved efficiency of the ZPM-2 composite ascribed to synergistic effect between P–MoS 2 and ZnS, which helps to lower the band gap of ZnS, shift absorption to the visible light region, promoting electron transfer and inhibit electron-hole recombination rate. Our study provides a new insight to develop novel photocatalyst for photocatalytic applications. • Synthesized ZnS/P-doped-MoS 2 photocatalyst with dual characteristics using in-situ precipitation method. • The UV light-active absorption edge of ZnS shifting toward the visible region. • The composite showed enhanced photocatalytic activity compare to ZnS and P–MoS 2. [ABSTRACT FROM AUTHOR]

The construction of heterojunctions is one of efficacious ways to improve the charge transfer and suppress the recombination of photoexcited electron-hole pairs for enhancing reactive activities of photocatalysts. Ternary NiS-ReS 2 /CdS composites are synthesized via a one-step hydrothermal method and the heterojunction nanostructures are achieved. The NiS-ReS 2 /CdS photocatalyst exhibits the superior photocatalytic activity with a hydrogen production rate up to 139 mmol g−1 h−1, which is much higher than binary composites and pure CdS. The contributions of the dual cocatalysts NiS and ReS 2 are verified to narrower bandgaps, lower resistances and increase photocurrent density of NiS-ReS 2 /CdS, promoting the absorption of visible light and the migration of photoinduced electrons. The NiS-ReS 2 /CdS heterostructures provide a possible dual Z-scheme path for the rapid transfer of electrons. The tailoring of the dual cocatalysts is effective to improve the photocatalytic hydrogen production. [Display omitted] • Ternary NiS-ReS 2 /CdS composites are fabricated via a one-step hydrothermal way. • NiS-ReS 2 /CdS exhibits the photocatalytic hydrogen production rate of 139 mmol g−1 h−1. • A suitable small amount of rhenium benefit to the high photocatalytic activity. • The heterostructures provide the dual Z-scheme paths to improve hydrogen production. [ABSTRACT FROM AUTHOR]

This study investigates the effect of Ag-doping on the (001) surface of SrTiO 3 (STO) to enhance hydrogen production via water-splitting employing density functional theory (DFT) simulations. It was found that the heterolytic water dissociation on Ag-doped (001)-STO occurs via a first-order reaction with an energy barrier of 5.74 kJ/mol, representing a reduction of 94% compared to undoped (001)-STO. The Gibbs free energy of H 2 formation catalyzed by Ag-doped (001)-STO is approximately −302 kJ/mol, indicating the spontaneity of this process. Additionally, the surface band gap energy decreases by ∼2 eV after water-splitting, suggesting charge transfer from the Ag-doped STO to the water and leading to new electron-hole recombination states. This research underscores the potential of Ag-doping in enhancing the efficiency of hydrogen production through water-splitting, contributing to the development of greener and more efficient energy technologies. • Ag-(001)-STO catalyzes H 2 formation spontaneously, indicating potential for hydrogen production. • Ag-doped (001)-STO reduces water dissociation energy barrier by 94%, enhancing catalytic activity. • Water interaction induces resonance states in Ag-doped (001)-STO, lowering band gap by 0.95 eV. • Electronic analysis reveals midgap and low electron mobility bands in transition state, crucial for water-splitting. • The study contributes to photocatalysis by elucidating Ag-doping impact in perovskite semiconductors. [ABSTRACT FROM AUTHOR]

Bi 2 WO 6 has attracted extensive attention in photocatalysts in recent years as a typical Aurivillius oxide. However, it suffers from severe electron-hole recombination due to the large charge transfer distance from bulk to surface. Unfortunately, strong chemical bonds between the neighboring layers in Aurivillius oxides lead to difficulties in the construction of 2D materials. Here, a facile NaBH 4 -assisted hydrothermal method is developed to construct 2D Bi 2 WO 6 nanosheets with adjustable thickness from 4.03 to 1.51 nm and O vacancies density (named as BWO-x, x = 15, 30, 45, 60). By balancing the thickness and the O vacancy density in the nanosheets, the charge separation efficiency can be tuned and consequently, the photocatalytic activity can be optimized, leading to over 11 times enhancement in photocatalytic hydrogen evolution. Furthermore, the best performed nanosheets demonstrate universality in dye polluted water treatment. Nearly 100% degradation can be reached after only 5, 50, and 30 min with degradation rate constant of 29.73, 3.21, and 6.62 min−1g−1 for Rhodamine B, methyl orange, and methylene blue, respectively. This work provides a comprehensive approach to produce ultrathin 2D nanosheets of Aurivillius photocatalysts for enhanced charge separation and photocatalytic activity. • Ultrathin 2D Bi 2 WO 6 nanosheets have been constructed. • Improved charge separation has been achieved in the ultrathin 2D BWO nanosheets. • The 2D BWO nanosheets exhibit enhanced photocatalytic H 2 evolution and dye degradation. • This work provides a comprehensive approach to produce ultrathin 2D nanosheets of Aurivillius Oxides. [ABSTRACT FROM AUTHOR]

In this research, TiO 2 -GO composites were prepared by combination process included sol-gel for synthesizing TiO 2 nanoparticles and afterward loaded GO on TiO 2 (NPs) with hydrothermal treatment in ethanol/water medium. The black TiO 2 –H nanoparticles and TiO 2 -rGO-H nanocomposites were prepared through simple thermal hydrogen treatment at 600 °C for 3 h. The synthesized nanoparticles and the composite catalysts were characterized by XRD, FESEM, FTIR analyzes and the BET (Brunauer–Emmett–Teller) surface area measurement. The results revealed that synthesized TiO 2 nanopowder was almost anatase phase with high crystallinity when coupled with GO leads to a decrease in the size of the crystallites by creation of smaller TiO 2 clusters in result of enhanced dispersion of TiO 2 on GO sheets. However, adding up GO has slightly improved optical properties of the photocatalyst samples. Compared with TiO 2 -GO composites, the high temperature (600 °C) hydrogenation produced anatase/rutile black TiO 2 -rGO nanocomposites enhanced hydrogen production rate 9 orders of magnitude higher than those observed for TiO 2 powders, reached values of more than 368 μ mol g− 1 h – 1. A significant reduction in the energy band gap of 2.72 eV (DRS results) and also decreasing the electron-hole recombination according to PL spectra results has been recorded for TiO 2 -rGO-H nanocomposite. In addition, the black TiO 2 nanoparticles and TiO 2 -rGO nanocomposites possessed much more concentration of oxygen vacancies and carrier concentration according to Raman analysis. • Photocatalytic improvement obtained in TiO 2 -rGO nanocomposite after hydrogen thermal treatment to reach black TiO 2 -rGO nanocomposite. • The hydrogen treatment process led to transition phase the part of anatase phase into rutile phase that promoted the electro-hole separation mechanism. • The high temperature (600 °C) hydrogenation enhanced hydrogen production rate 9 orders of magnitude higher than those observed for TiO 2 powders. [ABSTRACT FROM AUTHOR]

Low degradation rate for a long degradation time and poor cycle stability caused by rapid recombination of generated electron-hole pairs are tough challenges for photo-Fenton degradation The unique microstructure catalyst can provide enough catalytic surface to prevent the recombination of electron-hole pairs and facilitate the barrier-free transport of active species. In addition, the special hollow microsphere structure can effectively accelerate the Rhodamine B (RhB) penetration and the photo-Fenton process. Introducing SrWO 4 can increase oxygen vacancies and optimize the electronic structure of ZnFe 2 O 4 , thus enhancing electron transport and RhB degradation in the photo-Fenton process. This kind of catalytic material ZnFe 2 O 4 /SrWO 4 (ZFO/SW) in the photo-Fenton process can effectively degrade the 99.18 % RhB dye only within 20 min with remarkable cycling stability. This work demonstrates the high efficiency of ZFO/SW as a photocatalyst and confirms the contribution of the current design concept to the development of photo-Fenton degradation materials. [ABSTRACT FROM AUTHOR]

Globally, the emergence of drug-resistant bacteria has created an urgent need for an effective method to remove antibiotics from pharmaceutical wastewater. Engineering Bismuth vanadate (BiVO 4) with an oxygen evolution cocatalyst (OEC) holds a promising potential for enhancing water splitting efficiency in the production of hydrogen (H 2) using free solar energy. Here, we successfully developed a Zr:BiVO 4 /NiFeOOH heterojunction by electrodeposition and photoelectrochemical transformation. Zr:BiVO 4 /NiFeOOH photoanodes exhibit 5 fold superior photocurrent response at 1.23 V compared with Zr:BiVO 4 electrodes, since NiFeOOH acts as an oxygen-releasing catalyst. Furthermore, the attained heterojunctioned electrode can effectively degrade TCH, riboflavin, and streptomycin in PEC. The degradation rate of TCH acquired 96% within 1 h, which is 3 times superior than the efficiency reported for pristine Zr:BiVO 4 photoelectrodes. By introducing NiFeOOH into BiVO 4 , electron life-time was increased and electron-hole recombination was suppressed. In this study, we present a solar-driven, sustainable and effective way of treating wastewater and provide new insights into the process. [Display omitted] • Synthesis of Zr:BiVO 4 /NiFeOOH photoanodes via photoelectrochemical transformation process. • Synergistic effect of NiFeOOH co-catalytic layer over Zr:BiVO 4 electrodes with enriched PEC performances. • A photocurrent of 1.27 mA/cm2 with nearly 5-fold enhancement is achieved. • The electrodes demonstrated superior performance in the degradation of tetracycline hydrochloride using PEC. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalysts are promising for Oxygen evolution reaction (OER) and also for reducing organic pollutants in wastewater. However, their limited activity under UV light and the fast recombination of electron-hole pairs, hinder their utilization in wastewater treatment. To address these challenges a novel photocatalyst based on carbon quantum dots (CQDs) supported Zinc–Cobalt Oxide (ZnCo 2 O 4) was developed, which demonstrated enhanced photocatalytic efficiency. Experimental findings indicated that 0.7 CQDs/ZnCo 2 O 4 exhibited superior photocatalytic performance compared to ZnCO 2 O 4 and CQDs/ZnCO 2 O 4 composites materials, achieving over 100 and 96 % decomposition of methylene blue (MB) and methylene orange (MO) dyes after 50 and 140 min under UV light. The enhanced performance of 0.7 CQDs/ZnCo 2 O 4 can be attributed to the charge transfer rate and synergistic effect between the coupled CQDs and ZnCo 2 O 4. Moreover, studies with radical scavengers reveal that •O 2 , •OH, and h+ play crucial roles in the breakdown of MB and MO dyes. Furthermore, 0.7 CQDs/ZnCo 2 O 4 displayed very low overpotential of 220 mV at 100 mA cm−2 for OER activity with a robust durability for 250 h at 500 mA cm−2. • CQDs-decorated ZnCo 2 O 4 Mss was developed by facile impregnation-thermal methode. • The enhanced catalytic activity of CQDs/ZnCo 2O 4 is due to the n-p junction, which generatesholes, ●OH, and ●O 2−. • Optimized 0.70 CQDs/ZnCo 2O 4 achieves nearly100% MB degradation in 50 min. • The photocatalytic degradation mechanism of CQDs/ZnCo 2O 4 MSs enhanced charge separation and improve overall photocatalytic activity. [ABSTRACT FROM AUTHOR]

Photocatalytic natural seawater-derived splitting to produce hydrogen is one of the most potential strategies to alleviate the shortage of freshwater resources and energy crisis. Nevertheless, the complicated composition of natural seawater poses substantial challenges to the activity and stability of photocatalysts. Here, we report on the fabrication of carbon dots (CDs) and B elements co-modified carbon nitride (i.e. CDs/BCN) via precursor-mediated supramolecular self-assembly and subsequent NaBH 4 -assisted thermal reduction as well as its implementation as seawater-derived H 2 production. The fabricated CDs/BCN exhibits the flaky porous structure capable of providing more transport channels for the generated gases (e.g. H 2) and precipitates (e.g. Mg(OH) 2 , Ca(OH) 2) during the seawater splitting process. Benefitting from cooperation of CDs and B elements i.e. the inhibited recombination of electron-hole pairs as well as the extended optical absorption range of CN, the optimal CDs/BCN-2 under visible-light irradiation exhibits the high H 2 production rate up to 10369 μmol g-1 h-1 in natural seawater. The proven satisfactory reusability and the corresponding structural stability demonstrate the excellent corrosion resistance of CDs/BCN-2 in natural seawater. Additionally, CDs/BCN-20 photocatalyst synthesized via 20-fold precursor amplification procedure still displays efficient photocatalytic performance of 9022 μmol g-1 h-1, indicating its potential for industrial applications. [Display omitted] • CDs and B co-modified flaky porous CN is fabricated by a facile calcination method. • The optimized CDs/BCN-2 displays superb H 2 production activity in natural seawater. • The satisfactory stability of CDs/BCN exhibits its excellent corrosion resistance. • After amplification procedure CDs/BCN-20 exhibits high photocatalytic performance. [ABSTRACT FROM AUTHOR]

Bi 2 S 3 , Bi 2 MoO 6 and TiO 2 composite photoanodes were fabricated using three different preparation routes to improve its photoelectrochemical (PEC) stability. The microstructure of three photoanodes are distinct significantly according to the results of XRD, SEM and TEM. The ordered TiO 2 nanorod arrays (NRAs) and thinner Bi 2 MoO 6 sheet crystals in flower-ball structure facilitate carrier transport and suppresses electron-hole recombination efficiently. The results of PEC tests indicate that the photoanode with Bi 2 MoO 6 sheet crystals in flower-ball structure and TiO 2 NRAs shows significant enhancement in PEC performance stability due to its ordered microstructure facilitating carrier transport and transfer and also good adherence of photoanode layer on FTO glass substrate. This photoanode in Bi 2 S 3 quantum dots/Bi 2 MoO 6 @TiO 2 NRAs structure exhibits satisfactory properties, achieving a PEC stability of 86.41% after 48 h. [Display omitted] • Three photoanodes were fabricated in various preparation routes. • PEC performance of three photoanodes were analyzed based on their different Microstructure. • The PEC stability of Bi 2 S 3 QDs/Bi 2 MoO 6 @TiO 2 NRAs photoanode is up to 86.41% after 48 h. [ABSTRACT FROM AUTHOR]

Recently, piezo-catalytic technology with low cost, simplicity and feasibility are drawing more attention in the field of water pollution remediation; nevertheless, the catalytic activity of diverse piezoelectric materials is limited by the rapid recombination of electron-hole pairs and low carrier mobility. Herein, a collaborative strategy of entropy and defect engineerings is proposed to enhance the piezo-catalytic activity of BaTiO 3 -based materials ((1- x)BaTiO 3 - x Sm(Ca 0.2 Zn 0.2 Zr 0.2 Sn 0.2 Hf 0.2)O 3). As x increases, the configuration entropy of the materials is greatly increased from 0 R to 1.3227 R, suggesting that the ceramics with x = 0.05, 0.10, 0.15 and 0.20 possess significantly increased disordering and the ferroelectric long-range order is broken, rendering the materials rich in catalytically active sites and thus enhancing the catalytic performance. In addition, the doping of multiple ions with different ionic radii and valence states leads to abundant oxygen vacancies inside the material, thereby enabling easier separation and migration of electron-hole pairs and resulting in enhanced catalytic activity. Accordingly, the high-configuration-entropy 0.90BaTiO 3 -0.10Sm(Ca 0.2 Zn 0.2 Zr 0.2 Sn 0.2 Hf 0.2)O 3 material with abundant oxygen vacancies exhibits outstanding piezo-catalytic activity, giving the reaction rate constant k of 38.7 × 10−3 min−1 for rhodamine B (RhB). Simultaneously, the 0.90BaTiO 3 -0.10Sm(Ca 0.2 Zn 0.2 Zr 0.2 Sn 0.2 Hf 0.2)O 3 material also show favorable catalytic activity for methylene blue (MB) and methyl orange (MO) with reaction rate constants k of 31.8 × 10−3 min−1 and 19.4 × 10−3 min−1, respectively. This work proposes a novel strategy for enhancing the piezo-catalytic activities of BaTiO 3 -based piezoelectric materials by the co-engineering of high-entropy doping and defect. [ABSTRACT FROM AUTHOR]

• Ag was atomically anchored on ultrathin carbon nitride by thermal polymerization. • Ag doping increased visible-light absorption and decreased the AgUTCN band gap. • Single-atom Ag favored O2 adsorption and subsequent O2•− formation. • O2•− was verified as the major contributor to photocatalysis by AgUTCN. • AgUTCN gives efficient photocatalytic degradation of various PPCPs. Carbon nitride has been extensively used as a visible-light photocatalyst, but it has the disadvantages of a low specific surface area, rapid electron–hole recombination, and relatively low light absorbance. In this study, single-atom Ag was successfully anchored on ultrathin carbon nitride (UTCN) via thermal polymerization, the catalyst obtained is called AgUTCN. The Ag hardly changed the carbon nitride's layered and porous physical structure. AgUTCN exhibited efficient visible-light photocatalytic performances in the degradation of various recalcitrant pollutants, eliminations of 85% were achieved by visible-light irradiation for 1 hr. Doping with Ag improved the photocatalytic performance of UTCN by narrowing the forbidden band gap from 2.49 to 2.36 eV and suppressing electron–hole pair recombination. In addition, Ag doping facilitated O 2 adsorption on UTCN by decreasing the adsorption energy from −0.2 to −2.22 eV and favored the formation of O 2 ·−. Electron spin resonance and radical-quenching experiments showed that O 2 ·− was the major reactive species in the degradation of Acetaminophen (paracetamol, APAP). [Display omitted] [ABSTRACT FROM AUTHOR]

Achieving precise control and optimization of structure and composition is paramount for advancing photocatalyst performance. In this study, we successfully synthesized nitrogen-defect and boron-doped one-dimensional g-C 3 N 4 nanotubes (BCNNT) with a tube diameter of approximately 100 nm using a one-step gas-phase self-assembly strategy. Intriguingly, the introduction of boric acid induced a transformation from a two-dimensional g-C 3 N 4 structure to a one-dimensional tubular form. The physicochemical properties and photocatalytic performance of BCNNT were found to be influenced by the quantity of boric acid employed. The as-synthesized BCNNT exhibited notable advantages, including enhanced visible light absorption, a 0.1 eV reduction in the band gap, 5.1 times increase in photocurrent density, effective suppression of electron-hole recombination, and significant improvement in mass transfer compared to pure g-C 3 N 4. Consequently, the first-order kinetic constant of BCNNT increased by 73.7 %, resulting in nearly 80 % degradation of tetracycline (TC) within half an hour. The boron doping played a crucial role in reducing the surface energy required for nanotube formation during synthesis, a key factor in their structural development. Both density functional theory (DFT) calculations and experimental studies confirmed that the Lewis acid site B enhanced tetracycline adsorption, while nitrogen-deficient sites suppressed electron-hole recombination, thus accelerating photocatalytic degradation rate. This research provides a novel perspective on fabricating tubular g-C 3 N 4 structures and compositions, offering insights for improving the kinetics of photocatalytic reactions. [ABSTRACT FROM AUTHOR]

In this study, a well-designed hierarchical BiFeO 3 /ZIF-67 (BFO-ZIF) composite was successfully synthesized to improve the performance of photocatalytic hydrogen generation in comparison to bare BiFeO 3 and ZIF-67. Moreover, the behavior of the resultant electrocatalysts was also investigated in the hydrogen evolution reaction (HER). The synthesized electro-photocatalysts were characterized by various physical and photo/electrochemical analyses. The remarkable outcomes of the composite with 50 wt% of ZIF-67 in hydrogen generation correspond to the high specific surface area of the photocatalyst concurrently with the formation of active sites and new charge channels, leading to a modified charge transfer pathway and lower electron-hole recombination. The maximum H 2 generation rate over the optimal BFO-ZIF composite (BFO-ZIF(50)) attained 1617 μmol g−1 h−1 during visible light exposure, surpassing the rates observed for pure BFO and ZIF-67. Furthermore, the BFO-ZIF(50) electrocatalyst, with the onset potential of −0.089 V, resulted in an overpotential of −0.19 V at a current density of 10 mA cm−2, while a Tafel slope of 81.6 mV dec−1 in 1.0 M KOH showed the highest activity. The elevated photocatalytic hydrogen generation and improved HER performance of the developed catalysts signify a synergistic effect resulting from the junction and the Z-scheme charge transfer mechanism between the ZIF-67 and BFO nanomaterials. This introduces the BFO-ZIF composite as an efficient photocatalyst and electrocatalyst for hydrogen generation and evolution reaction. • Photocatalytic hydrogen generation and HER were studied by BiFeO 3 /ZIF-67 composites. • The maximum hydrogen generation rate of 1617 μmol g−1 h−1 is achieved. • The optimal electrocatalyst exhibited the overpotential of −0.19 V (10 mA cm−2). • High activity is attributed to the synergistic effect between the ZIF-67 and BiFeO 3. [ABSTRACT FROM AUTHOR]

The quest for sustainable and efficient renewable energy sources has escalated in recent years, with photocatalytic hydrogen production gaining prominence due to its potential to harness solar energy for clean fuel generation. In this study, we design 2D/2D heterostructure CuInS 2 :In 2 S 3 /g-C 3 N 4 nanosheets utilizing electrostatic interaction for hydrogen evolution reaction under visible light irradiation. Integrating CuInS 2 :In 2 S 3 and g-C 3 N 4 layers to form an interfacial 2D:2D heterostructure results in a broad light absorption range, effective charge separation, and excellent stability. The heterostructure ensures efficient interfacial charge transfer pathways, mitigating electron-hole recombination and promoting hydrogen evolution. The hybrid nanosheets prepared with the hydrothermal method exhibited ∼40-fold synergistic enhancement in hydrogen production and long-term stability. The synergistic boost in activity resulted from the formation of S-scheme heterojunctions (CuInS 2 /g-C 3 N 4 and CuInS 2 /In 2 S 3) within hybrid nanosheets. [Display omitted] • CuInS 2 :In 2 S 3 /g-C 3 N 4 (CNCIS) nanosheets were synthesized using methods like self-assembly, photoreduction, and hydrothermal. • The CNCIS photocatalyst produced hydrogen at a rate of 917 μmol/h/g when TEOA was used as the sacrificial agent. • The composite CNCIS achieved a 40-fold synergistic boost in H 2 production compared to its individual components CN and CIS. • A dual S-Scheme heterojunction charge transfer mechanism is proposed. [ABSTRACT FROM AUTHOR]

The photocatalytic efficiency of graphitic carbon nitride (g-C 3 N 4) in hydrogen production is primarily hindered by its poor absorption of visible light, rapid recombination of electron-hole pairs, and the absence of hydroxyl radical formation. Herein, a novel g-C 3 N 4 nanosheets functionalized with sulfonic acid groups were effectively produced through thermal polymerization of melamine and 2, 4-diamino-6-phenyl-1, 3, 5-triazine (DPT), followed by sulfonation treatment. The introduction of the phenyl group brings about alterations to the initial symmetrical arrangement of g-C 3 N 4 , leading to the disruption of certain hydrogen bonds. This, in turn, facilitates the movement of electrons from the n to π* orbitals, resulting in enhanced light absorption and improved efficiency in charge separation. Moreover, it induces modifications to the band structure and amplifies the production of hydroxyl radicals. Additionally, the introduction of sulfonic acid enhances the water affinity and the ability of dispersing graphitic carbon nitride in water. The optimized sulfonated benzene-substituted g-C 3 N 4 (1000-BCN-SO 3 H) with a melamine to DPT ratio of 4:1 exhibits a maximum hydrogen production rate of 6.52 mmol·h−1·g−1 under simulated sunlight irradiation with good cycling stability, which is 3.93 times higher than that of g-C 3 N 4 nanosheets. This research offers a promising opportunity for a novel approach in advancing carbon nitride materials for effective photocatalytic processes. [Display omitted] • Sulfonated benzene functionalized g-C 3 N 4 was prepared by thermal polymerization and sulfonation reactions. • Sulfonation created many voids and enhanced the hydrophilicity and water dispersion. • The increased absorption at 490 nm was due to the process of n→π* excitation. • 1000-BCN-SO 3 H nanosheets exhibit excellent photocatalytic performance and stability. • The hydrogen evolution of 1000-BCN-SO 3 H is 3.93 times that of pure g-C 3 N 4. [ABSTRACT FROM AUTHOR]

Donor-acceptor conjugated polymers have received significant attention as the most promising photocatalysts for efficient photocatalytic hydrogen production (PHP). Nonetheless, achieving high photocatalytic PHP performance relies on molecular framework design and the judicious selection of different structural units. Herein, benzotrithiophene (BTT) and triazine derivatives were used as the basic units of organic polymers, and two conjugated porous polymers (CPPs) named as CP1 and CP2 were successfully synthesized by Stille coupling reaction. Compared with benzene as the linkage unit of triazine, it is evident that the incorporation of the thiophene unit in CP2 broadens its light response range, and promotes the generation of electrons/holes induced by light. Density functional theory (DFT) calculations and femtosecond transient absorption(fs-TA) spectroscopy reveal that CP2 effectively inhibits the photogenerated electron-hole pair recombination and promotes carrier transport. Remarkably, CP2 with Pt co-catalyst exhibited a notably superior PHP performance compared with that of CP1 polymer, which achieved an impressive hydrogen evolution rate (HER) of 21702.4 μmol/g/h, surpassing CP1 by approximately 3.7 times. This work provides a new tactic for enhancing the intrinsic PHP activity and reveals the underlying mechanism for the enhanced photocatalytic activity by regulating the different structural units of the donor-acceptor conjugated polymers. [Display omitted] • Two conjugated porous polymers were constructed based on benzotrithiophen and triazine derivatives. • Polymers CP1 and CP2 were prepared from benzene and thiophene linked triazine derivatives, respectively. • The different linkage units contribute to the great difference in photocatalytic performance. • CP2 exhibited an ultrahigh hydrogen evolution rate 21702.4 μmol/g/h. • The thiophene unit in CP2 suppress recombination of photo-induced charge carriers and promote transport. [ABSTRACT FROM AUTHOR]

Nowadays, environmental problems are increasingly varied and the development of various diseases. Due to its ability to create defect in band gap energy and strong antibacterial activity against a variety of microorganisms, ZnO is used to solve both issues. However, ZnO has a large band gap energy, so it is necessary to decrease band gap by doping. In this study, the synthesis of ZnO and ZnO doped materials (N- and (Mg,B,N)-doped ZnO) through the solid-state was carried out. The phases of doped ZnOs are hexagonal wurtzite, according to the results of the characterization using XRD, Raman spectroscopy, and HR-TEM. Surface morphology for N-doped ZnO does not form agglomeration, while in (Mg,B,N)-doped ZnO, agglomeration occurs due to the difference in charge of B with Zn. The existence of dopant in ZnO lattice was confirmed by EDS and XPS. (Mg,B,N)-doped ZnO has the highest specific surface area (14.388 m2/g) according to the BET analysis. The formation of peaks in 358 nm, 520 nm, and 650 nm during PL examination indicates a reduction in the rate of electron-hole recombination and defects. The recombination rate was confirmed by EIS Nyquist spectra result. The band gap energy owing to doping decreased from 3.13 eV to 3.10 eV and 3.12 eV for N- and (Mg,B,N)-doped ZnO, respectively. The lifetime of undoped ZnO, N-doped ZnO, and (Mg,B,N)-doped ZnO is 0.526, 0.610, and 0.695 ns, respectively. Photocatalyst test results showed that N-doped ZnO and (Mg,B,N)-doped ZnO materials were optimum for degradation of methyl violet for under visible light with degradation efficiency of 89.28 % and 93.24 %, respectively. N-doped ZnO and (Mg,B,N)-doped ZnO produce inhibition zone of 7.18 mm and 14.15 mm for Escherichia coli bacteria and 7.50 mm and 11.80 mm for Staphylococcus aureus bacteria. Additionally, molecular docking studies were used to explain a potential mechanism for in vitro bacterial activity. [ABSTRACT FROM AUTHOR]

Hydrogen is becoming more widely accepted as a potential energy carrier due to zero emissions, superior energy capacity, and ecological sustainability. It can be produced in a number of ways, but photocatalytic water splitting using sunlight has recently attracted attention as a sustainable option. Photocatalysts based on semiconductors, especially TiO 2 photocatalysts, have been the subject of extensive study because of their desirable physicochemical properties. There are still obstacles to overcome, however, including a wide bandgap, sluggish electron-hole recombination, and the potential for excessive H 2 generation. Numerous strategies such as doping, defect engineering, dye sensitization, and semiconductor coupling have been investigated with the goal of improving the performance of TiO 2 by discovering solutions to these limitations. This article summarizes current research on the multiple parameters affecting the photocatalytic process in dynamic H 2 generation. Surface area, particle size, TiO 2 loading, pH, temperature, light source, light intensity, sacrificial reagents, and band gap energy are all important characteristics of photocatalysts. The techno-feasible analysis, current challenges, possibility for subsequent research, and the potential for H 2 production by the photocatalytic water-splitting process are further addressed in this article. [Display omitted] • Recent attempts involving TiO 2 -based photocatalysts to produce H 2 via photocatalytic water-splitting have been addressed. • Various strategies to improve TiO 2 photocatalytic efficiency have been proposed for practical applications. • Factors affecting the TiO 2 -based photocatalytic efficiency were reviewed. • Techno feasibility analysis water-splitting have been addressed for commercialization. • Several challenges, future perspectives and strategies for development have been proposed. [ABSTRACT FROM AUTHOR]

Direct Z-schemes for photocatalytic overall water splitting for hydrogen generation are constructed for Sc 2 CCl 2 /MoTe 2 and Sc 2 CCl 2 /Hf 2 CO 2 heterostructures on the basis of the calculated band alignment and built-in electric field. Solar-to-hydrogen efficiency (η STH ′), which is evaluated using the overpotentials of the band edges and band gaps, can reach 22.09 % for Sc 2 CCl 2 /MoTe 2 and 19.07 % for Sc 2 CCl 2 /Hf 2 CO 2. Tensile strains have little effect on η STH ′. Compressive strains substantially increase the η STH ′ of Sc 2 CCl 2 /MoTe 2 and boost that of the Sc 2 CCl 2 /Hf 2 CO 2 heterostructure only slightly. Nonadiabatic dynamics simulations reveal that the lifetime of the photogenerated electron in one of the stacking patterns of Sc 2 CCl 2 /MoTe 2 is much larger than that of the other configurations, indicating that the reduction ability of the electron is well protected. However, the interlayer electron–hole recombination in Sc 2 CCl 2 /MoTe 2 is faster than that in Sc 2 CCl 2 /Hf 2 CO 2 , implying that the Z-schemes with the former are more efficient than the Z-schemes with the latter. The hydrogen and oxidation evolution reactions with the two heterostructures are thermodynamically feasible but the reactions cannot proceed spontaneously. These findings provide a helpful guide for the development of photocatalytic materials for photocatalytic hydrogen generation from overall water splitting based on the title heterostructures. [Display omitted] • Maximum solar-to-hydrogen efficiency of the constructed schemes can reach 22.09 %. • 4 % compressive biaxial strain can boost the efficiency of Sc 2 CCl 2 /MoTe 2 to 33.77 %. • Reduction ability of SM-AA is well protected by its long electron transfer time. • Minimum Gibbs free energy of HER/OER on the heterostructures reaches 0.89/1.99 eV. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have emerged as highly promising photocatalysts for solar-driven water splitting. They have garnered significant interest owing to their large specific surface areas and short carrier migration distances. Our study focused on the theoretical prediction of promising photocatalysts for solar-driven water splitting in XAu 4 Y (X, Y= Se, Te) monolayers and their corresponding heterostructures using first-principles calculations. XAu 4 Y are semiconductors with indirect bandgaps of 1.27–1.54 eV. Owing to their appropriate band edges, SeAu 4 Se and SeAu 4 Te were found to be suitable for solar-driven water splitting. Importantly, SeAu 4 Te achieved a Janus-induced internal electric field of 0.80 V/Å, which favored the separation of photogenerated carriers, thus improving the photocatalytic efficiency. Further, SeAu 4 Se/TeAu 4 Te and SeAu 4 Se/TeAu 4 Se heterostructures were predicted to be high-performance Z(S)-scheme photocatalysts for hydrogen evolution with strong redox abilities, efficient separation of photogenerated carriers, and enhanced light absorptions. Our findings may provide valuable insights for realizing high-performance photocatalysts for water splitting. [Display omitted] • SeAu 4 Se and SeAu 4 Te are promising solar-driven photocatalysts for water splitting. • Janus SeAu 4 Te achieve a built-in electric field to restrain electron-hole recombination. • SeAu 4 Se/TeAu 4 Te, SeAu 4 Se/TeAu 4 Se, and TeAu 4 Te/SeAu 4 Te are staggered band alignments. • SeAu 4 Se/TeAu 4 Te and SeAu 4 Se/TeAu 4 Se are efficient Z(S)-scheme charge transport mechanisms. [ABSTRACT FROM AUTHOR]

• A Novel photocatalytic composite was made using recycled polyethylene (PE) and CaLaCoO 9 (LCCO) microplates. • The LCCO photocatalyst produced a maximum degradation of 96% for the MZ. • The fastest and complete MZ removal is reached when the initial pH of the contaminated solution is 3. • The OH and O 2 − radicals were the main oxidizing agents produced for the degradation of MZ. • The presence of the oxygen vacancy defects in the LCCO powders enhanced the degradation of MZ. Metamizole (MZ) is a widely used anti-inflammatory drug. Due to its common use, this contaminant is found in sewage and rivers. In order to reduce the contamination produced by the MZ, we fabricated in this work a photocatalytic composite using recycled polyethylene (RPE) and the CaLaCoO 9 (LCCO) perovskite. Those nanoparticles had a microplate-like morphology and sizes of 1.4–5.5 µm according to the analysis of microscopy. The photocatalytic properties of the LCCO powders were evaluated under ultraviolet-visible (UV-Vis) irradiation and found a removal efficiency of 96%. When the RPE+LCCO composite was employed for the photocatalytic degradation of MZ, a maximum degradation of 92.5% was obtained. The influence of the pH on the photocatalytic activity was also studied and found that an initial pH = 3 produced a total degradation of MZ after 240 min of UV-Vis irradiation. Moreover, three reuse cycles were carried out for the pure LCCO powders and for the RPE+LCCO composites and found that the maximum loss of degradation was 5%. Furthermore, scavenger experiments demonstrated that the super oxide and hydroxyl radicals are formed during the photocatalytic reaction and were responsible for the degradation of MZ. Additionally, the X-ray photoelectron-spectroscopy and Raman analysis demonstrated the formation of defects (oxygen vacancies), those ones delayed the electron-hole recombination, which in turn, enhanced the degradation of the MZ. Thus, the studies performed in this work proved that composites made with recycled plastics and LCCO perovskites are a low-cost and feasible alternative for the cleaning of water sources polluted with pharmaceutical compounds. [Display omitted]. [ABSTRACT FROM AUTHOR]

Utilizing photocatalysts devoid of noble metals for solar hydrogen production is a viable option in resolving the rising energy crisis. However, the current photocatalytic performance is inadequate due to the insufficient conversion of solar energy into storable chemical energy. Photocatalysts with bulk-twinned homojunction for enhanced photocatalytic performance have received attention in recent years. In addition, it has been demonstrated that introducing sulfur vacancies is an effective approach to improving the photocatalytic performance of metal sulphides. A key factor in increasing photocatalyzed solar hydrogen production is the charge separation and limiting their recombination using stacking fault. Herein, we synthesized novel nanocrystal solid solutions of twinned wurtzite/zinc blende, Cd x Zn 1-x S (x = 0.1, 0.3, 0.5, 0.7 and 0.9), having rich sulfur vacancies. The solid solutions were prepared via a facile alkaline-assisted hydrothermal pathway, and then the activity, morphology, and surface properties were correlated using extensive characterization techniques. It was found that the Cd 0·5 Zn 0·5 S solid solution with twinned homojunction and rich sulfur vacancies exhibited a higher solar hydrogen production activity and stability than the bare Cd 0·5 Zn 0·5 S solid solution. [Display omitted] • Cd x Zn 1-x S solid solutions were synthesized via an alkaline-assisted hydrothermal pathway. • Twinned homojunctions boost the separation of photoexcited electrons and holes. • Sulfur vacancies serve as adsorption sites and traps for electron-hole recombination. • Optimized twinned crystals Cd 0·5 Zn 0·5 S with sulfur vacancies, had the highest H 2 production rate of 850 μmol (h. g cat)−1. [ABSTRACT FROM AUTHOR]

Flexible pressure sensors have recently attracted increasing attention. Piezoresistive sensors are widely used in wearable devices, human health monitoring, electronic skin, human-computer interactions, and other fields owing to their good sensitivity and rapid response. The assembly of a pressure sensor using SnO 2 –ZnO hybrid nanofibers is proposed in this study to improve its performance. The heterojunction at the interface between ZnO and SnO 2 facilitates electron transfer from SnO 2 to ZnO by suppressing electron-hole recombination and accelerating electron motion in ZnO. The scaffold sensor, as compared to other reported pressure sensors, exhibits better flexibility, optimized sensitivity, and pressure sensing range, and can detect dynamic pressure over a wide range (0–60 kPa). The sensor exhibits strong sensitivity (11.5 kPa−1), fast response and recovery times of 42 and 28 ms, respectively, and durable cyclic stability (600 cycles). This sensor can quickly detect human motion from subtle deformations, including weak changes in the joints of the fingers, wrists, and elbows, with a bending degree of approximately 20°. Owing to its excellent performance, breathability, and washability, it can be directly attached to skin or clothing for long-term use and has broad application prospects in wearable electronics. [ABSTRACT FROM AUTHOR]

Efficient photocatalysts nurture great potential for harnessing sunlight to produce chemical energy, a pivotal step towards sustainable fuel production. However, designing such systems poses significant challenges due to the complex interaction between light absorption and charge carrier dynamics. In an attempt to address these challenges, this study introduces a novel approach, combining bulk-twinned homojunction Cd x Zn 1-x S photocatalysts with sulphur vacancies. These Cd x Zn 1-x S photocatalysts are seamlessly integrated with molybdenum disulfide (MoS 2) to optimize photocatalytic properties and enhance charge transfer via the formation of heterojunctions. Due to its unique crystal structure, the twinned homojunction in Cd x Zn 1-x S enhances light absorption and charge carrier generation. The integrated sulphur vacancies perform several functions: they expediate light adsorption and inhibit electron-hole recombination. These vacancies were initially introduced into the bulk structure during Cd x Zn 1-x S solid solution synthesis. Further, MoS 2 provided an augmentation at the surface modification level, thus enhancing their functional role and amplifying their impact on the overall photocatalytic efficiency. The heterojunction formed between MoS 2 and Cd x Zn 1-x S provides an integrated efficient platform for overall performance. The composite nanocrystals, wurtzite/zinc-blende twinned MoS 2 /Cd x Zn 1-x S, were synthesized via an N, N-dimethylformamide-assisted solvothermal method. Detailed characterization was conducted to establish correlations among activity, morphology, and surface properties. The resulting composite photocatalysts demonstrated improved solar hydrogen generation activity and stability, surpassing the performance of twinned crystal Cd x Zn 1-x S. [Display omitted] • Sulphur vacancies enhance the photocatalytic activity of Cd x Zn 1-x S/yMoS 2. • Defects within the twinned structure play a key role in charge carrier separation. • MoS 2 surface modification expands the light-harvesting windows of photocatalysts. • Composite photocatalysts demonstrate superior stability in hydrogen production. [ABSTRACT FROM AUTHOR]

To address the inherent limitations of ZnS and MoS 2 as visible light photocatalysts, herein, we report a step-by-step tuning of mixed sulfide composite system (ZnS/MoS 2) to achieve enhanced visible light to hydrogen fuel conversion efficiency in the absence of any sacrificial agents. In the first stage, ZnS/MoS 2 composite was synthesized by using a single step hydrothermal route and the photocatalytic activity of the synthesized ZnS/MoS 2 composite was tuned by varying the ratio of Zn and Mo in the composite. In the second stage, the photocatalytic efficiency of the composite was further enhanced by tuning the band gap and visible light absorption characteristics of the material through cobalt doping (Co-doping) in the MoS 2 co-catalyst. The hydrogen generation activity of the tuned composition (1:1.3 ratio of Zn and Mo) of the ZnS/MoS 2 composite with 3% Co-doping is obtained as the best (1256 μmol of H 2 in 1 h) as compared to the other compositions of the doped composites (1%, 3% and 5% Co doping). The enhanced hydrogen generation through visible light induced water splitting of the developed mixed sulfide composite systems (ZnS/MoS 2 and ZnS/Co-doped MoS 2) even in the absence of any sacrificial agents is ascribed to their tuned band gap and low electron-hole recombination rate. • Step-by-step tuning of morphology and band gap of ZnS/MoS 2 photocatalyst. • Flower-like ZnS/MoS 2 composite with highly porous morphology achieved through a one-step hydrothermal method. • ZnS/Co-doped MoS 2 system with tuned band gap and low electron-hole recombination rate. • Mixed sulfide composite systems with enhanced photocatalytic activity even in the absence of any sacrificial agents. • Offers a facile strategy for the step-by-step tuning of the photocatalytic mixed sulfide composites. [ABSTRACT FROM AUTHOR]

The practical implementation of photocatalytic hydrogen generation faces challenges due to the rapid recombination of photogenerated electron-hole pairs. This study reports the synthesis of a WSP/g- C 3 N 4 S-scheme heterojunction catalyst featuring exposed hydrogen evolution active W sites, achieved through in-situ P introducing. Remarkably, the WSP/g-C 3 N 4 catalyst exhibits a superior photocatalytic hydrogen evolution rate of 3.92 mmol h−1 g−1, surpassing g-C 3 N 4 and attaining 112 times the performance of pristine C 3 N 4. A series of characterization techniques and Density functional theory (DFT) reveal that WSP/C 3 N 4 possesses the following advantages as a photocatalyst: 1) Under visible light irradiation, the distinctively ordered and well-crystallized structure generates potential differences, facilitates charge transfers, and enhances the hydrogen evolution activity. 2) The coupling between WSP and g-C 3 N 4 interfaces effectively promotes the directional migration of photogenerated electrons. 3) The shallow bound energy level introduced near the conduction band of WSP effectively prolongs the carrier lifetime. These features collectively contribute to the improved performance of photocatalytic hydrogen evolution. These features collectively contribute to the improved performance of photocatalytic hydrogen evolution. This finding suggests new ways to create organic/inorganic heterojunction composite photocatalysts for efficient hydrogen generation. • WSP and g-C 3 N 4 have S-scheme charge transfer. • Interface engineering establishes a fast electron transmission path. • The performance of WSP/g-C 3 N 4 photocatalytic hydrogen production is significantly improved, and it has high reusability. • The shallow bound energy level introduced near the conduction band of WSP effectively extends the carrier lifetime. [ABSTRACT FROM AUTHOR]

We investigate anatase TiO 2 doping with Au to determine the change in the band gap energy and optoelectronic properties using experimental and theoretical analysis. The structural analysis using XRD patterns revealed that the synthesized materials primarily exhibited an anatase phase of TiO 2 , with no impurity peaks observed. However, as the concentration of Au increased, additional diffraction peaks corresponding to Au crystalline phases were detected, indicating successful doping. Furthermore, the crystallite size was found to decrease with increasing Au concentration. We observe that the band gap reduces through substitution of Au into the TiO 2 lattice from 3.09 eV to 2.78 eV, demonstrating the feasibility of bandgap tuning of the TiO 2 system. A redshift for Au doped TiO 2 is observed from absorption spectroscopy and optical absorption intensity using hybrid density functional theory, facilitating visible light absorption, although with potential electron-hole recombination limitations. To enhance a visible light photocatalytic activity for water splitting, we extend our work to explore the impact of N and Au codoping into TiO 2 lattice. It reveals that the combination between N and Au leads to a suitable reduction in the band gap width of pure TiO 2. Interestingly, Au–N codoping may decrease the effect of photogenerated carriers, produce a new optical absorption feature in the visible region, and enhance the photocatalytic performance of TiO 2. This codoping configuration is also a promising photocatalyst for the decomposition of water using visible light without inducing unoccupied states. • Analyzing Au doped TiO2's geometry and optoelectronic features experimentally and theoretically. • Favorable O-rich environments promote the formation of Au doped TiO 2 structures. • Substituting Ti with Au causes a redshift in absorption edges, impacting energy band gaps. • Using hybrid density functional calculations to compute electronic and optical properties. • Codoping Au and N atoms to narrow band gap of TiO 2 without introducing impurities, enhancing visible spectrum photocatalysis. [ABSTRACT FROM AUTHOR]

Organic pollutants, such as dyes, contaminated water bodies seriously. Suitable materials and efficient technologies for degrading pollutants needed to be explored to protect the environment and human health. In this investigation, PVDF(PAA-g-β-CD)@TiO 2 hybrid film was prepared by a combination of "in situ hydrothermal-vapor induction" under mild conditions. The distribution, particle size, and interaction with the film surface for TiO 2 were investigated by XRD, XPS, SEM, and EDS. The TiO 2 nanoparticles were firmly immobilized and uniformly distributed on the hybrid film surface. Poly (acrylic acid) (PAA) and β-cyclodextrin (β-CD) on the film matrix were connected by the chemical bond, which provided stable nucleation and growth sites for TiO 2 while inhibiting photogenerated electron-hole recombination and significantly enhancing the adsorption ability. Furthermore, the multiple interaction forces (hydrogen bonding, coordination, and hydrophilic-hydrophilic interactions) between the film matrix and the TiO 2 were evaluated by simulated geometries and theoretical calculations. The multiple interactions reduced the band gap (Eg) while endowing the hybrid photocatalytic film with excellent degradation efficacy (η), stability, and recycling properties. Finally, the η of methylene blue (MB) reached 97.34 % within 120 min and remained above 90 % even after 8 reuses. It was believed that PVDF(PAA-g-β-CD)@TiO 2 film provided an approach for the mild preparation of polymer/TiO 2 hybrid film with high catalytic activity and optimization of photocatalytic properties. [Display omitted] • PVDF@TiO 2 hybrid membranes were fabricated by the "in situ hydrothermal-vapor induction". • The TiO 2 nanoparticles were immobilized and highly uniformly distributed on the membrane surface. • PAA and β-CD promoted charge transfer and boosted the "adsorption-photocatalysis" process. • The effects of the size and distribution of TiO 2 on the photoactivity were revealed. • The multiple interactions between TiO 2 and the matrix endowed the hybrid membrane with long-term stability. [ABSTRACT FROM AUTHOR]

Active S atoms of sulfides play key roles in photocatalytic H 2 production. This study reports a visible-light-driven ZnIn 2 S 4 photocatalyst with abundant active S atoms achieved by exposing more (110) plane via adjusting S contents in reactants. The prepared samples exhibit flower-like microparticles aggregated by nanosheets (∼10 nm thick). The aggregation increases with the S contents. XRD and XPS results indicate that ZIS-1 exposes more (110) planes and active S atoms than other samples. Photocatalytic H 2 production tests indicate that ZIS-1 exhibits the highest H 2 production rate (19.81 mmol g−1 h−1) and AQY value (19.36 %) among the prepared samples. The underlying reason for the high performance of ZIS-1 is attributed to the active S mechanism, which is confirmed by the phenomenon that the photocatalytic performance decreases when secondary materials are modified on its surface. Furthermore, the optical and electrochemical experiments suggest that the ZIS-1 owns more photogenerated electrons, less electron-hole recombination rates, higher donor density, and better charge transfer ability. This study may provide a new idea for rational design and simple synthesis of high-performance and cost-effective metal sulfide semiconductor photocatalysts for solar-hydrogen energy conversion. [Display omitted] • ZnIn 2 S 4 microflowers with various amounts of active S atoms were prepared. • ZIS-1 shows the highest H 2 production rate under visible light irradiation. • Exposing more (110) planes leads to the higher amount of active S atoms. • More active S atoms are mainly responsible for the high performance of ZIS-1. [ABSTRACT FROM AUTHOR]