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Hierarchically porous CNT@NC@GCN membranes with high porosity of 85% are fabricated facilely, the 3D hierarchical porous network can provide broad reaction interface and active sites for LiPSs anchoring. Furthermore, the uniform GCN layer can significantly improve the metallicity and conductivity of the frameworks, and strengthen Li+ and electron transport. The abundant N in the GCN coating can enrich active sites in the membrane for adsorption and catalysis conversion of LiPSs and Li 2 S at a low energy barrier. [Display omitted] Various challenges remain to be overcome in lithium-sulfur (Li-S) batteries, including the volume expansion and low conductivity of sulfur, the shuttle effect of lithium polysulfides and the sluggish redox reaction in the cell. Herein, we propose a multilayered conductive framework by the in situ growth of a conformal graphene-like C 3 N 4 (GCN) coating on porous CNT@NC networks with carbon nanotubes (CNTs) as the core and N -doped carbon (NC) as the crosslinking shell. The abundant N in the GCN coating increased the surface N concentration of the framework from 14.38% to 18.77%, which enriched the active sites in the frameworks for the adsorption and catalysis conversion of LiPSs and Li 2 S with a low energy barrier. Furthermore, the scalable frameworks can provide an 85% porosity for a sufficient reaction interface and accommodate the volume expansion of sulfur. The synergistic effect between GCN and the highly conductive hierarchical structure can accelerate the transport of Li+ and electrons as well as the diffusion of electrolyte. Benefitting from the above advantages, the Al-free CNT@NC@GCN electrode exhibits a reversible capacity of 647.6 mAh g−1 after cycling for 450 cycles at 1C with a low capacity fading rate of 0.09% per cycle. This proposed facile strategy creates inspiring insights into the design of novel cathode materials for Li-S batteries. [ABSTRACT FROM AUTHOR]

This paper mainly studies the adsorption of C3N4 on a series of heavy metals and focuses on the adsorption performance of C3N4 on Nd and Th. The main conclusions are as follows: Through the use of the thermal stripping method and melamine as the raw material, C3N4 was obtained at a lower cost, with superior adsorption performance. Through SEM-EDS, TEM, and other characterization analyses, the results show that C3N4 has a clear multilayer sheet structure, and the surface of the material is more uniformly dispersed. The maximum adsorption capacity of C3N4 for Th is 86.6 mg.g-1, and the maximum adsorption capacity for Nd is 60.1 mg.g-1. The kinetic model is also used for fitting, and the results showed that the kinetic of the adsorption was in line with the pseudo-second-order model, indicating that the adsorption was chemical interaction. After C3N4 adsorbed heavy metal elements, it was characterized by SEM-EDS, TEM, UHRTEM, and AFM. The results showed that a variety of heavy metal ions can be adsorbed by C3N4, which proved that C3N4 has good adsorption performance. Due to factors such as metal particle size, the adsorption of C3N4 on heavy metal elements is different. [ABSTRACT FROM AUTHOR]

The previous research addressed the waste problem of agriculture and forestry residues by exploring the efficient utilization of liquefied soybean straw in supercapacitor. The structures of the liquefied soybean straw were controlled by coupling microwave hydrothermal treatment with carbonization under the influence of a C 3 N 4 bifunctional template. What's more, C 3 N 4 could effectively regulate the pore structures and provide an effective N active site of carbon materials C 3 N 4. The obtained N-SLR Carbon-700 possess a specific surface area of up to 1593.7 m 2  g -1 , and the pore size is mainly concentrated in the range of 1.8-2.5 nm, providing efficient ions transmission channels and storage space. Its specific capacitance is up to 261.5 F g -1 (current density of 0.5 A g -1 ), and the capacity retention is 74.04 % when the current density is expanded by 20 times. In the two-electrode system, the energy density of N-SLR Carbon-700 could reach to 31.3 W h kg -1 at a power density of 360 W kg -1 , as well as the energy surface density is maintained at 69 % when the power density is increased by a factor of 20. This work enhances effectively the charging and discharging stability and capacitance value of carbon-based supercapacitor., (© 2024 Wiley-VCH GmbH.)

Establishing efficient and clear atomic-level charge transfer channels presents a significant challenge in the design of effective photocatalysts. A sound strategy has been developed herein involving the construction of defect-induced heterostructures that create chemical bonds serving as charge transfer channels at the heterojunction interface. In situ XPS, alongside theoretical calculations, demonstrates the successful construction of Zn-O/N-C as atomic charge transfer channels. Our findings reveal that the introduction of zinc vacancies (V Zn ) reduces the carrier transport activation energy (CTAE) from 155.2 meV for ZIS/CN to 128.7 meV for V Zn -ZIS/CN. Consequently, the optimal V Zn -ZIS/CN achieves a high hydrogen evolution rate of 22.26 mmol g -1 h -1 without Pt as a cocatalyst, which is approximately 57 times greater compared to that of ZIS/CN. Notably, hydrogen is generated at bubble levels under natural sunlight. This work provides insights into the mechanisms by which defect-induced heterostructure building strategies can introduce chemical bonds at the heterojunction interface.

ZrO2/carbon nitride (C3N4) composite photocatalysts were prepared by solid-state grinding and subsequent calcination. They were characterized by X-ray diffraction, scanning electron microscopy, UV–Vis diffuse reflectance spectroscopy, and photoluminescence spectroscopy. Their photocatalytic activity was evaluated by the degradation of methylene blue (MB). Results showed that the grain size of the C3N4/ZrO2 composite photocatalyst was relatively small at about 10 nm. HRTEM showed that a heterojunction was formed between ZrO2 and g-C3N4. Under the assistance of H2O2, the visible-light degradation activity of MB by the composites was much higher than that by pure ZrO2. The 9%g-C3N4/ZrO2 composite photocatalyst had the best photocatalytic performance, and it could degrade 99% of MB in 60 min. Adding a small amount of NaCl to the solution had a significant effect on the photocatalytic effect of the composite. Such addition could inhibit the photocatalytic activity of samples with high C3N4 content and significantly improve the performance of photocatalysts with low C3N4 content. The 1%g-C3N4/ZrO2 composite (assisted by H2O2) had the best photocatalytic effect on the MB solution containing salt. It could degrade MB solution containing 0.15, 0.3, and 0.6 g/L NaCl within 30, 40, and 45 min, respectively. [ABSTRACT FROM AUTHOR]

The significant increase of NOx concentration causes severe damages to environment and human health. Light-driven photocatalytic technique affords an ideal solution for the removal of NOx at ambient conditions. To enhance the performance of NOx removal, 1D, 2D and 3D photocatalysts have been constructed as the light absorption and the separation of charge carriers can be manipulated through controlling the morphology of the photocatalyst. Related works mainly focused on the construction and modification of special morphologic photocatalyst, including element doping, heterostructure constructing, crystal facet exposing, defect sites introducing and so on. Moreover, the excellent performance of the photocatalytic NOx removal creates great awareness of the application, which has promising practical applications in NOx removal by paint (removing NOx indoor and outdoor) and pavement (degrading vehicle exhausts). For these considerations, recent advances in special morphologic photocatalysts for NOx removal was summarized and commented in this review. The purpose is to provide insights into understanding the relationship between morphology and photocatalytic performance, meanwhile, to promote the application of photocatalytic technology in NOx degradation. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) is an organic semiconductor for photocatalysis. However, it still suffers from low surface area and rapid e–/h+ recombination, which limits its further activity enhancement. In this work, an atomically precise alkynyl- and phosphine-protected Ag33(4-MePhCC)22(Dppp)4 nanocluster is synthesized. It is facilely loaded onto g-C3N4 nanosheets by a one-step process. The resulting Ag33/g-C3N4 nanocomposite is thoroughly characterized. Its activity is evaluated in the photodegradation of methyl orange. Ag33/g-C3N4 has shown a 16-fold activity enhancement compared to pristine g-C3N4. The mechanism investigation using UV–vis/diffuse-reflectance spectroscopy spectra, photocurrent response, and Nyquist plots has revealed the origin of this superior performance. [ABSTRACT FROM AUTHOR]

Adsorption of dichlorodiphenyltrichloroethane (DDT) on titanium dioxide supported on graphitic carbon nitride (TiO2/cGN) was investigated using a novel, accurate and broadly parametrized self-consistent tight-binding quantum chemical (GFN2-xTB) method. The adsorption energy, charges on atoms, bond orders and reaction pathway have been determined and analyzed to figure out the nature of the adsorption process. The obtained results indicate that the adsorption of DDT on the pristine cGN is physical of nature. The combination of TiO2 and cGN significantly enhanced the material's adsorption performance. DDT is chemically adsorbed on TiO2/cGN due to the formation of chemical bonds between atoms of DDT and TiO2/cGN. In addition, the adsorption process does not involve a transition state. [ABSTRACT FROM AUTHOR]

[Display omitted] • The R ct value of Ti 4 O 7 -C 3 N 4 (5.445 Ω·cm2) was reduced by 66.05 % compared with Ti 4 O 7. • The degradation ratio of IMD with Ti 4 O 7 -C 3 N 4 was as high as 99.18 % in 1.256 min. • The removal of IMD in the actural Wanjiang water with Ti 4 O 7 -C 3 N 4 was up to 81.12 %. Imidacloprid (IMD) is a kind of neonicotinoid insecticide, which is widely used in the agricultural production. There are few reports on electrocatalytic degradation of IMD with the low concentration. In this study Ti 4 O 7 -C 3 N 4 electrode was employed for the first time to electrocatalytically degrade low concentration IMD. Compared with pure Ti 4 O 7 electrode, the oxygen evolution potential was increased from 1.84 V to 2.50 V, the charge transfer resistance (R ct) was reduced by 66.05 %, and the oxygen vacancies were increased by 2.5 times compared to the original Ti 4 O 7. Especially, the R ct for Ti 4 O 7 (5.45 Ω·cm2) was only 1/7 of that for boron-doped diamond (BDD) (38.89 Ω·cm2). IMD degradation ratio was up to 98 % in only 1.256 min (75.360 s) using a Ti 4 O 7 -C 3 N 4. When SongShan Lake water, Wanjiang water, and secondary effluent were treated, the degradation radios of IMD were 70.30 %, 72.33 % and 81.12 %, respectively. In the presence of Cl− coexisting ions, no disinfection by-product of ClO 4 − was detected, which is an advantage for Ti 4 O 7 -C 3 N 4 compared with BDD. The first and 48th degradation ratios were 99 % and 97 %, respectively, indicating the good stability of Ti 4 O 7 -C 3 N 4. The development of Ti 4 O 7 -C 3 N 4 provides a stable, low energy consumptions and no secondary pollution anode for the treatment of actual wastewater. [ABSTRACT FROM AUTHOR]

Based on the random method combining with group and graph theory (RG2), a new chiral (P3 2 21) framework is discovered, which can be considered as the second crystalline allotrope of C 3 N 4 with mixed sp2 and sp3 bonding features similar to the previously synthesized P4 3 2 1 2 phase [ Physical Review B, 94, 094,106, 2016 ]. P3 2 21 is both dynamically and mechanically stable, and it is energetically more favorable than the superhard and dense α-phase and β-phase at ambient conditions. The calculated band structures show that P4 3 2 1 2 and P3 2 21 are indirect band gap insulators with energy gaps of 3.452 eV and 3.542 eV and their Vicker's hardness are confirmed to be 10. 98 GPa and 22.79 GPa, respectively. It is interesting that the simulated E-P and E-V curves show that P3 2 21 will be more favorable than P4 3 2 1 2 after 19 GPa and it possesses an opportunity to survive within a certain volume interval. [Display omitted] [ABSTRACT FROM AUTHOR]

Photocatalytic oxidative desulfurization (PODS) presents a sustainable and cost-effective alternative to conventional diesel desulfurization techniques. In this study, various methodologies, including ultrasonic dispersion, sol-gel and impregnation, were employed to prepare Anderson-type polyoxometallates (POMs) (NH) 4 H 6 ZnMo 6 O 24 derived ZnMo 6 /C 3 N 4 , composites for PODS. The photocatalytic properties of these composites were thoroughly characterized using various techniques. The synergistic effect between ZnMo 6 nanoclusters and C 3 N 4 sites significantly enhanced their photocatalytic activity in the visible light region. The incorporation of ZnMo 6 increases the surface energy of C 3 N 4 and enhances its electrons capture capacity, thereby reducing the electron-hole pair recombination rate and suppressing its photoluminescence intensity. Computational analysis reveals that the adsorption energy of dibenzothiophene (DBT) and charge transfer capacity are markedly enhanced upon ZnMo 6 doping into C 3 N 4. The optimized catalyst (50 % ZnMo 6 /C 3 N 4) exhibited 100 % desulfurization rate with low catalyst dosage and O/S ratio within only 2 h. Importantly, negligible decay in performance is observed over five consecutive reuses, indicating its robust stability in PODS. This investigation provides a comprehensive model and theoretical framework for the multifunctional PODS system, demonstrating its potential for practical application. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, MoS 2 /C 3 N 4 composites are prepared using a simple hydrothermal method, with alterations made to the weight of the g-C 3 N 4 precursor, to explore the influence of C 3 N 4 amount on lithium storage ability and other properties such as morphological/structural change. The support of C 3 N 4 enhances the electronic conductivity of MoS 2 and reduces the volume change of MoS 2 as it undergoes continuous charging and discharging. Besides, the good formation of MoS 2 /C 3 N 4 heterostructure, which is generated by the appropriate addition of the precursors, supplies more active sites for Li+ and leads to faster ionic diffusion rate and electronic transfer speed. Profiting from the above advantages, the MCN-100 could retain excellent reversible capacity of 533.2 mAh/g even under ultrahigh current of 5 A/g after 100 cycles and exhibited superior rate performance of 1414.4 mAh/g at 1 A/g. [Display omitted] ● The influence of addition amount of C 3 N 4 in the MoS 2 /C 3 N 4 composites is investigated. ● The morphology evolution of MoS 2 /C 3 N 4 composites with the increasing C 3 N 4 is unveiled. ● MCN-100 possesses the morphology of flower-like microspheres with stable interface through the robust N-Mo bond. ● MCN-100 presents superior electrochemical lithium storage properties. [ABSTRACT FROM AUTHOR]

Due to the fact that the luminescence of Eu3+ belongs to orbital forbidden f → f transition, the luminous intensity of Eu3+-activated phosphors is relatively weak. In this work, in order to increase the luminous intensity of GdPO 4 :Eu3+, a series of GdPO 4 :Eu3+@g-C 3 N 4 phosphors was obtained via conventional solid-state reaction, with GdPO 4 :0.05Eu3+@0.005 g-C 3 N 4 identified as the optimal sample. The characterization results indicate that: (a) The coating of g-C 3 N 4 not only enhances the luminescence, but also unexpectedly induces a relatively weak negative thermal quenching (NTQ) effect, thereby obviously improving its luminescence thermal stability. The mechanisms behind the enhanced luminescence and luminescence thermal stability are explored, and attributed energy transfer from g-C 3 N 4 to Eu3+ and phonon electron interaction, respectively. (b) The WLED prepared with GdPO 4 :0.05Eu3+@0.005 g-C 3 N 4 and yellow fluorescent phosphor (YAG:Ce3+) forms warm-white light under excitation of ultraviolet light. The findings reveal that GdPO 4 :0.05Eu3+@0.005 g-C 3 N 4 is a potential candidate for using in the field of warm WLEDs excited by ultraviolet light. [Display omitted] • GdPO 4 :0.05Eu3+@0.005 g-C 3 N 4 has been synthesized. • Emission of Eu3+ is enhanced by 0.005 g-C 3 N 4. • Sample has weak negative thermal quenching effect. • Mechanism of negative thermal quenching effect is discussed. [ABSTRACT FROM AUTHOR]

C3N4 is an innovative material that has had huge success as a photocatalyst in recent years. More recently, it has been coupled to robust metal oxides to obtain more stable materials. This work is focused on the different synthesis techniques used to prepare bare C3N4 and combined C3N4/ZnO mixed systems. Different precursors, such as pure melamine and cyanuric acid-based supramolecular complexes, were employed for the preparation of the C3N4 material. Moreover, different solvents were also used, demonstrating that the use of water leads to the formation of a more stable heterojunction. Structural (XRD), morphological (FESEM) and optical (UV-vis) measurements underlined the role of the precursors used in the preparation of the materials. A clear trend can be extrapolated from this experimental approach involving different intimate contacts between the two C3N4 and ZnO phases, strictly connected to the particular preparation method adopted. The use of the supramolecular complexes for the preparation of C3N4 leads to a tighter association between the two phases at the heterojunction, resulting in much higher visible light harvesting (connected to lower band gap values). [ABSTRACT FROM AUTHOR]

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Generally, C3N4 was widely used in the field of photocatalytic hydrogen production, but only few studies focused on electrocatalytic hydrogen production field in Ni/Co based systems. Herein, to investigate the enhanced HER property of C3N4, NiCo2O4@C3N4 were fabricated successfully via a simple mixture method. With the introduction of C3N4, NiCo2O4@C3N4 showed better HER property with small overpotential (89 mV, η10 mA cm−2), low Tafel slope (146 mV dec−1) and superior long‐term stability, thereby indicating the excellent synergistic effect between NiCo2O4 and C3N4. Besides, compared with NiCo2O4, the large electrochemically active surface areas of NiCo2O4@C3N4 (ca. 126 cm2) indicated the abundant active sites, directly proofing the HER enhancement of C3N4. According to Density Functional Theory (DFT) calculation results, when NiCo2O4 combined with C3N4, the EH2O* of NiCo2O4@C3N4 decreased from 3.80 to 2.76 eV and, accordingly, the heterostructure possessed an appropriate ΔGH* (0.19 eV, close to Pt), suggesting the unique synergistic effect between NiCo2O4 and C3N4. Meanwhile, H2O interacted with the d orbital of the Co atom and induced more electrons to transfer from NiCo2O4 to C3N4 and H2O sequentially, thereby accumulating plenty of electrons on H2O molecule and further activating H2O molecule. Accordingly, the H−O−H bond angle of H2O was narrowed from 104.3° to 103.2°, meanwhile, the O−H bond length was extended from 0.975 to 0.989 Å, demonstrating the HER enhancement of C3N4. [ABSTRACT FROM AUTHOR]

Generally, C3N4 was widely used in the field of photocatalytic hydrogen production, but only few studies focused on electrocatalytic hydrogen production field in Ni/Co based systems. Herein, to investigate the enhanced HER property of C3N4, NiCo2O4@C3N4 were fabricated successfully via a simple mixture method. With the introduction of C3N4, NiCo2O4@C3N4 showed better HER property with small overpotential (89 mV, η10 mA cm−2), low Tafel slope (146 mV dec−1) and superior long‐term stability, thereby indicating the excellent synergistic effect between NiCo2O4 and C3N4. Besides, compared with NiCo2O4, the large electrochemically active surface areas of NiCo2O4@C3N4 (ca. 126 cm2) indicated the abundant active sites, directly proofing the HER enhancement of C3N4. According to Density Functional Theory (DFT) calculation results, when NiCo2O4 combined with C3N4, the EH2O* of NiCo2O4@C3N4 decreased from 3.80 to 2.76 eV and, accordingly, the heterostructure possessed an appropriate ΔGH* (0.19 eV, close to Pt), suggesting the unique synergistic effect between NiCo2O4 and C3N4. Meanwhile, H2O interacted with the d orbital of the Co atom and induced more electrons to transfer from NiCo2O4 to C3N4 and H2O sequentially, thereby accumulating plenty of electrons on H2O molecule and further activating H2O molecule. Accordingly, the H−O−H bond angle of H2O was narrowed from 104.3° to 103.2°, meanwhile, the O−H bond length was extended from 0.975 to 0.989 Å, demonstrating the HER enhancement of C3N4. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) has been paid increasingly attentions in U(VI) removal due to the visible-light response, whereas the high recombination of photogenerated electron and holes limited the actual environmental application. Herein, Z-scheme MoS2/g-C3N4 heterojunction was fabricated to enhance removal of U(VI) from aqueous solution. The microscopic and spectroscopic characterizations showed that addition of MoS2 on surface of g-C3N4 increased separation efficiency of photogenerated charge, decreased the bandgap and improved the intensity of light adsorption. Approximate 82% of UO22+ was photo-reduced by MoS2/g-C3N4 after 1 h of light irradiation at pH 4.5. The high effective photocatalytic reduction of U(VI) on MoS2/g-C3N4 was attributed to ·O2− radials according to quenching experiments. XPS analysis showed that the adsorbed U(VI) was photo-reduced into U(IV). These findings are crucial for the design of C3N4-based composites with high efficient photocatalytic performance and exclusive selectivity into actual environmental cleanup. [ABSTRACT FROM AUTHOR]

Due to the good photocatalytic performance, which ensures the decomposition of pollutants under light, g-C3N4 is considered as an ideal photocatalytic material. Montmorillonite has a high adsorption capacity and layered structure, which has positive effects on increasing the specific surface area of g-C3N4 and avoid its polymerization agglomeration. In this paper, montmorillonite was used as carrier for g-C3N4 to obtain a new photocatalytic composite g-C3N4/Mt. Then the morphological and (micro)structural properties were characterized. The well-characterized materials were evaluated for the photocatalytic activity in degradation of methylene blue and Bisphenol A. The effects of the mass fraction of g-C3N4, light irradiation time, and pollutant concentration on the photocatalytic performance of g-C3N4/Mt composites were studied. Under the optimal experimental plan, the rate of photocatalytic degradation can reach to 99.3% within 120 min. Through the MS spectrum, it can be found that methylene blue molecule were catalysed and degraded into many harmless substances with low-molecular weight. Finally, based on the obtained reaction products, the mechanism by which the pollutants are removed was proposed. This study provides a new strategy to improve the photocatalysis ability of g-C3N4, which is of great significance for a sustainable pollution treatment. [ABSTRACT FROM AUTHOR]

Hydrogen, as an important clean energy source, is difficult to store and transport, which hinders its applications in real practice. Developing robust yet affordable storage media remains to be a challenge for scientists. In this study, Ab Initio Molecular Dynamics (AIMD) simulations were employed to evaluate the performance of aluminum (Al) decorated carbon nitride (g-C3N4, heptazine structure) in hydrogen storage; and a benchmarking study with Mg-doped g-C3N4 was also performed to provide theoretical insights for future study. We found that each 2 × 2 supercell can accommodate four Al atoms, and that partial charge from single Al sites can be transferred to adjacent nitrogen atoms of g-C3N4. These isolated Al sites tend to be electronically positive charged, serving as active sites for H2 adsorption, predominately by triggering enhanced electrostatic interactions. The H2 molecules are adsorbed by both Al and N atoms, and are easily polarized, giving rise to electrostatic interactions between the gas molecules and the surface. Effective adsorption sites were determined by electronic potential distribution maps of the optimized configurations. Each 2 × 2 supercell can adsorb up to 36 H2 molecules, and the corresponding adsorption energies are within the range of −0.10 to −0.26 eV. The H2 storage capacity of the Al-decorated g-C3N4 is 7.86 wt%, which surpasses the goal of 5.5 wt%, set by the US department of energy. This proposed Al-decorated g-C3N4 material is therefore predicted to be efficient for hydrogen storage. This work may offer some fundamental understandings from the aspect of electronic sharing paradigm of the origin of the excellent hydrogen storage performance by metal decorated 2D materials, acting as an demonstration for guiding single metal atom site-based materials’ designing and synthesis.

Photoassisted electrocatalysis is a frontier direction of electrocatalysis for promoting energy conversion. In this work, a metal-free C 3 N 4 /Se-CNTs is reported as a novel catalyst for photoassisted electrocatalytic oxygen evolution reaction (OER). C 3 N 4 has an appropriate bandgap, high specific surface area, and long-term stability. CNTs can modulate the electronic environment of C 3 N 4 by strong π-π interaction and greatly enhance the separation efficiency of photogenerated carriers. The distributed Se nanoparticles in CNTs can further increase the charge transfer ability. As a metal-free catalyst, the C 3 N 4 /Se-CNTs exhibits an overpotential of 231 mV at a current density of 10 mA cm -2 and a small Tafel slope of 52 mV dec -1 under illumination, which ranks among the best catalysts for photoassisted OER performance, surpassing most noble and transition metal-based catalysts. The result demonstrates the great potential of C 3 N 4 -based catalysts in the photoassisted OER process and provides a new perspective to explore the excellent metal-free OER catalysts.

In this paper, type-I C 3 N 4 -based isotype heterojunction was prepared. In photocatalyisis-self-Fenton reaction, it displayed high H 2 O 2 yield, outstanding utilization efficiency, and excellent degradation performance. The finding was beneficial to simultaneously solve two problems in traditional Fenton reaction: the source of H 2 O 2 and low utilization efficiency. [Display omitted] Herein, a type-I phosphorus-doped carbon nitride/oxygen-doped carbon nitride (P-C 3 N 4 /O-C 3 N 4) heterojunction was designed for photocatalysis-self-Fenton reaction (photocatalytic H 2 O 2 production and following Fenton reaction). In P-C 3 N 4 /O-C 3 N 4 , the photoinduced charge carriers were effectively separated with the help of internal-electric-field near the interface, ensuring the high catalytic performance. As a result, the production rate of H 2 O 2 in an air-saturated solution was 179 μM·h−1, about 7.2, 2.5, 2.5 and 2.1 times quicker than that on C 3 N 4 , P-C 3 N 4 , O-C 3 N 4 , and phosphorus and oxygen co -doped C 3 N 4 , respectively. By taking advantage of the cascade mode in photocatalysis-self-Fenton reaction, H 2 O 2 utilization efficiency was remarkably improved to 77.7%, about 9.0 times higher than that of traditional homogeneous Fenton reaction. Befitting from the superior yield and utilization efficiency, the degradation performance of P-C 3 N 4 /O-C 3 N 4 was undoubtedly superior than other photocatalysts. This work well addressed two bottlenecks in traditional Fenton reaction: source of H 2 O 2 and their low utilization efficiency, and the findings were beneficial to understand the mechanism and advantage of the photocatalysis-self-Fenton system in environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] To deal with unwanted biofouling adsorption, which impacts the economy and the environment, significant research has been devoted to composite systems involving a photocatalyst combined with self-renewal resin to provide synergistic antifouling. Here, photocatalyst based on three-dimensional (3D) network of carbon–oxygen-doped nitrogen-deficient carbon nitride and acrylic fluoroboron polymer as a system was successfully synthesized. 3D networks carbon nitride with carbon–oxygen dopants and nitrogen defects were prepared as skeletons, which effectively support and regulate the hydrolysis rate of the polymer. These composite systems exhibits excellent diatom anti-adhesion performance and high antibacterial rates for Escherichia coli and Staphylococcus aureus of up to 91.87% and 88.52%, respectively. In addition, self-cleaning function of the composite system are proved by and higher efficiency of chemical oxygen demand (COD) removal owing to efficient charge-carrier separation and transfer within the 3D network carbon nitride network. The great potential applications of this strategy demonstrated in marine engineering in the future. [ABSTRACT FROM AUTHOR]

Herein, composites of Co-doped graphitic C3N4 nanosheets and TiO2 nanoparticles (Co-C3N4 NSs/TiO2 NPs) were prepared through a two-step synthetic strategy, and their electrorheological (ER) performance under varied electric field strengths was also researched. The microstructure, chemical elements, and surface morphology of materials were studied thoroughly by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Brunauer–Emmett–Teller (BET) test, and X-ray photoelectron spectroscopy (XPS) measurements. The presence of TiO2 NPs and g-C3N4 was confirmed by XRD and FTIR results. Typical SEM and TEM images revealed the apparent sheet-like nanostructure of Co-C3N4, and the filling of TiO2 NP in-layers was discovered. Meanwhile, BET results indicated the abundant pore structure of Co-C3N4 NSs/TiO2 NP composites. The ER performances of Co-C3N4 NSs/TiO2 NP composites, including shear stress, shear viscosity, and ER efficiency, were examined under different electric field strengths with a high-quality electrorheometer. Interestingly, the obtained Co-C3N4 NSs/TiO2 NP composites exhibited an excellent ER property including an unexpected ER efficiency (up to 196), superior platform area, obvious dielectric loss peak, and high shear stress (more than 600 Pa at 3.0 kV/mm), showing wide application prospects as electrorheological materials. [ABSTRACT FROM AUTHOR]

The shape-dependent performance of metal co-catalysts in photocatalysis has been one of the research focal points in recent years. In this study, PtPd/C3N4 hybrid structures were constructed to reveal the effect of the shape of the PtPd bimetallic co-catalyst on the performance of photocatalytic hydrogen generation. PtPd nanocubes (NCs) and nanotetrahedrons (NTs) were sequentially deposited in situ on the surface of C3N4 nanosheets, establishing a strong contact interface to ensure the smooth transfer of photoinduced electrons. Ultraviolet–visible (UV–Vis) diffuse reflectance spectroscopy and photoelectrochemical experiments revealed that the PtPd NCs/C3N4 photocatalyst had comparable light absorption ability and equivalent carrier separation and transfer efficiency in comparison with the PtPd NTs/C3N4 photocatalyst, which excluded the influence of these factors on shape-dependent performance. The photocatalytic hydrogen generation results indicate that the hydrogen generation rate of the PtPd NCs/C3N4 photocatalyst is 1.33 times higher than that of the PtPd NTs/C3N4 photocatalyst, demonstrating that the cubic PtPd bimetallic co-catalyst is more conducive to hydrogen generation compared to the tetrahedral PtPd bimetallic co-catalyst. [ABSTRACT FROM AUTHOR]

Photoreforming (PR) of biomass can be considered a viable technology under mild experimental conditions to produce hydrogen with a high reaction rate using compounds from renewable resources and waste materials. The application of biomass PR gives rise to both hydrogen generation and biomass waste valorization. The process could be scaled up to obtain hydrogen under natural sunlight irradiation, and research on polymeric carbon nitride (g-C3N4)-based photocatalysts has been widely carried out in recent years. The non-metallic-based carbon nitride materials are economical and (photo)stable polymer semiconductors, and their physicochemical surface and electronic properties are optimal for obtaining H2, which can be considered a gas that does not cause major environmental problems. Some hindrances related to their structure, such as the low absorption of visible light and the relatively high recombination rate of electron-hole pairs, restrict the performance; therefore, it is necessary to improve their activity and the yield of the reaction by modifying them in various ways. Various types of solutions have been proposed in this regard, such as, for example, their coupling with other semiconductors to form composite materials. The current mini-review aims to overview the PR field, reporting some of the most interesting papers devoted to understanding the role of g-C3N4 in biomass PR. Information on many physico-chemical aspects related to the performance of the process and possible ways to obtain better results than those present up to now in the literature will be reported.

In order to effectively deal with chromium pollution in the environment, a heterojunction catalyst Ni@C _3 N _4 was prepared via in situ method. The nickel particles were deposited on the surface of O-C _3 N _4 . With the synergistic effect of O-C _3 N _4 and nickel particles, The Cr(VI) could be reduced completely to Cr(III) within 20 min at the present of Ni@C _3 N _4 under ultraviolet irradiation. Therefore, the composite photocatalyst had demonstrated that it could play an important role in the field of heavy metal wastewater treatment.

[Display omitted] • Deep eutectic system of ZrCl 4 /urea is devised to uniformly incorporate Zr with C 3 N 4. • Fluoride adsorption capacity of CN-Zr reaches 145.34 mg/g in hydrochloric acid. • Various Zr sources are considered on the performance and metal leaching rate. • Structural features and fluoride existence form in acid are considered in mechanism. • The adsorption cost of 0.3157 CNY/g indicates substantial industrial applicability. The fluorine chemical industry's rapid growth demands efficient strategies for treating and utilizing the costly and inefficient byproduct, fluoride-containing hydrochloric acid, posing a significant challenge. In this study, a cost-effective method was developed for preparing an acid-resistant and efficient defluorination material. Carbon nitride (C 3 N 4) was chosen for its exceptional acid resistance and was modified via template-free doping with different zirconium source. Characterization results through XRD, FTIR, BET, XPS, SEM, and TEM confirm the successful synthesis of CN-Zr using zirconium chloride (ZrCl 4) with a specific surface area of 87.77 m2/g. Furthermore, the adsorption results indicate outstanding fluoride adsorption performance of CN-Zr in hydrochloric acid, with a maximum adsorption capacity of 145.34 mg/g and minimal zirconium leaching. Moreover, the adsorption mechanism was systematically studied using Zeta potential, FTIR and XPS characterization. The findings indicate that Zr was integrated with C 3 N 4 uniformly by forming a deep eutectic system (DES), utilizing exposed terminal amino groups for effective hydrogen bonding with HF which predominates as the primary fluorine existence in hydrochloric acid. Meanwhile, the enhanced ion exchange, complexation of Zr-F and strong electrostatic attraction all contribute to improving adsorption. Finally, the assessment of recyclability performance and operation cost demonstrate that the material can maintain 80% of its initial adsorption capacity after five cycles. The cost analysis results indicate that the adsorption cost is only 0.3157 CNY/g, making it considerable competitive in the industry. [ABSTRACT FROM AUTHOR]

Constructing heterojunctions has emerged as a widely embraced strategy for augmenting piezo-photocatalytic activities. However, the synergistic pressure response, the construction of charge transfer, polar direction sites and active site are often left in the basket. Here, the carboxylated C 3 N 4 and Bi 2 MoO 6 S-scheme heterostructure was elaborately designed for piezo-photocatalytic nitrogen oxidation towards nitric acid. Extensive research evidence proves that Bi-COOH interaction between Bi 2 MoO 6 and g-C 3 N 4 leads to the occurrence of polarity interaction and structural reconstruction. Those initiatives facilitate the efficient distribution of charges and acts as a pathway for carrier migration, thereby promoting charge transfer and the large intrinsic dipole moment. Furthermore, the combination of polarity interaction and structural reconstruction strengthens N 2 polarization and electron transfer, facilitating the breaking of N N bonds and reducing activation energy. Consequently, the optimal BCO-3 catalyst revealed outstanding nitric acid production rates of 5930 μg g−1 h−1 under the stimulation of ultrasonic and light illumination, which is 3.66 times higher than that of C 3 N 4 -Bi 2 MoO 6 heterostructure and superiors to various piezo-photocatalysts. Our research endeavors present promising prospects for the design of advanced catalysts and contribute to a profound comprehension of molecular activation processes in heterojunction. [Display omitted] • Synergistic polarity interaction and structural reconstruction in Bi 2 MoO 6 / carboxylated C 3 N 4 heterojunction. • Bi-COOH interaction leads to the occurrence of polarity interaction and structural reconstruction. • Bi-COOH interaction facilitate the efficient distribution of charges and acts as a pathway for carrier migration. • It strengthens the polarization, activation, and adsorption of N 2. • Bi 2 MoO 6 /C 3 N 4 exhibited excellent piezo-photocatalytic activity and stability. [ABSTRACT FROM AUTHOR]

Triethylamine is a vital chemical raw material, but its leakage will pollute the environment and harm human health. It is particularly important to achieve detection of triethylamine. Here, PdRu nanoparticles, ZnO long-grained nanoparticles and C 3 N 4 were prepared for the identification of low concentrations of triethylamine. The response value of the sensor based on PdO-Ru/ZnO-C 3 N 4 1 to 20 ppm triethylamine was 96 at 220 °C. Furthermore, the lowest detection amount of it was as low as 50 ppb. And the time for rapid detection of 20 ppm triethylamine was shown to be 1 s. Besides, a circuit was designed to detect triethylamine in real time and raise the alarm when the concentration of triethylamine exceeded a threshold. The catalytic ability of PdRu nanoparticles and the formation of n-n heterojunction between ZnO and C 3 N 4 were conducive to enhancing the sensing performance. This work provides a way for monitoring of triethylamine and timely warning in chemical plants. [Display omitted] • PdO-Ru/ZnO-C 3 N 4 1 showed a high response (R a /R g = 96) to 20 ppm triethylamine at 220 °C. • The sensor had a short response time of 1 s • The lowest detection amount of PdO-Ru/ZnO-C 3 N 4 1 was as low as 50 ppb. • A circuit was designed to detect triethylamine in real time and could raise the alarm. [ABSTRACT FROM AUTHOR]

Two different synthetic approaches such as thermal decomposition method and microwave-assisted procedure were compared for the synthesis of nanosized ZnO. The two procedures were tested using zinc acetate as precursor as is, or in the presence of two coadjutants, one of anthropic origin (melamine) and one derived from the reuse of agricultural waste (wine extracts). All the samples were physico-chemically characterized in order to evaluate the influence of the synthesis conditions on the properties of the materials that were characterized by N 2 adsorption/desorption at 77 K and Field Emission-Scanning Electron microscopy measurements for evaluating the morphology, X-ray diffraction for examining the crystalline structure and X-Ray photoelectron spectroscopy for evidencing the surface composition of the nanoparticles. In order to verify the influence of the synthesis procedure on the electrical and optical properties of the ZnO nanoparticles, forecasting their use in photocatalytic applications, also the band gap of materials was evaluated by means of UV–Vis spectroscopy and Tauc plot. A final comparison of all the results allowed to evidence advantages and disadvantages of the procedures under study pointing out the importance of deepen the study of microwave-based synthetic approaches. [Display omitted] • ZnO is easily produced by thermal decomposition (TD) and microwave-assisted (MW) procedures. • MW method produces higher specific surface area samples, influencing nps size, with respect to TD approach. • Melamine influence ZnO nps optical properties with the shift of band gap due to C3N4 formation. • Sustainable ZnO synthesis is due to use of green chemicals, eco-friendly solvents and low-energy impact procedures. [ABSTRACT FROM AUTHOR]

Perovskite materials have shown great application prospects in the field of photocatalysis due to their excellent photoelectric properties. However, the toxicity of lead and material instability limit its application. In this work, the heterojunction based on C 3 N 4 thin layer encapsulated lead-free Cs 3 Bi 2 Br 9 nanocrystals was constructed by electrostatic self-assembly method. This combination way does not disrupt the electronic, crystalline and structural properties of C 3 N 4 and Cs 3 Bi 2 Br 9. Fluorescence quenching in C 3 N 4 /Cs 3 Bi 2 Br 9 composite is ascribed to the charge transfer process, which could be directly observed by spatially and temporally resolved fluorescence mapping image. The synergistic effect between C 3 N 4 and Cs 3 Bi 2 Br 9 can significantly improve the photocatalytic degradation efficiency of RhB, 98 % at 1 h. The stability of the composite was enhanced due to the special encapsulation effect. This work will provide a guideline for the construction of two-dimensional materials and perovskite heterojunction systems in the field of photocatalysis. • C3N4 encapsulated Cs 3 Bi 2 Br 9 nanocrystals heterojunction was constructed. • The band alignment between C 3 N 4 and Cs 3 Bi 2 Br 9 favors charge transfer. • Charge transfer process was directly visualized by fluorescence lifetime mapping. • This special combination way is conducive to improving the stability of Cs 3 Bi 2 Br 9. • Photocatalytic degradation efficiency of RhB for the composite reaches 98 % at 1 h. [ABSTRACT FROM AUTHOR]

Photoreduction of CO 2 and H 2 O into fuels and value-added chemicals is a promising green technology for solar-to-chemical conversion. However, improving the conversion efficiency with regulated product selectivity is a big challenge due to the sluggish dynamic transfer and insufficient active sites. Herein, we report on Pt single atoms anchored porous C 3 N 4 nanosheet photocatalyst (Pt 1 @CN) with Pt–N 4 coordination for stable and efficient CO 2 photoreduction using H 2 O as reductant. The Pt 1 @CN exhibits an evolution rate of 84.8 μmol g−1 h−1 with nearly 100% CO selectivity, outperforming most previous C 3 N 4 -based single-atom photocatalysts. Experimental and DFT calculation results reveal that the Pt–N 4 coordinated active sites promote the photogenerated electron transfer, CO 2 adsorption/activation, *COOH generation, and *CO desorption, thus accounting for the significantly improved CO 2 photoreduction activity with ∼100% CO selectivity. This study provides a deep insight into the significant roles of single-atom active sites in enhancing the CO 2 photoreduction activity and regulating the product selectivity. [Display omitted] • Pt single atoms anchored porous C 3 N 4 nanosheets (Pt 1 @CN) photocatalyst is synthesized via a facile pyrolysis process. • Pt 1 @CN exhibits efficient CO 2 photoreduction with nearly 100% CO selectivity using H 2 O as a reductant. • Single-atom Pt–N 4 active sites promote CO 2 adsorption, *COOH generation, *CO desorption, and charge separation/transfer. [ABSTRACT FROM AUTHOR]

[Display omitted] • The nanoparticle/spindle-shaped FeS and FeO on folded nanosheets of various 2D materials were successfully synthesized. • FeS/FeO containing 2D-TiO 2-x exhibits high and stable photocatalytic oxidation of CIP using PPS and H 2 O 2 oxidants. • The mechanism is a type Z-heterojunction with strong electric and magnetic characteristics. • FeS/FeO@TiO 2 black-C 3 N 4 exhibited high photoelectrocatalytic HER capacity at lower overpotential. The soft magnetic FeS 2 /Fe 2 O 3 (FeS/FeO)-incorporated 2D C 3 N 4 and TiO 2-x nanomaterials were successfully synthesized and characterized by various physicochemical techniques, including XRD, FTIR, XPS, HRTEM, UV–Vis, VSM-magnetism and PL. The photocatalytic performance of the materials was applied to activate potassium persulfate (PPS) and H 2 O 2 for the antibiotic ciprofloxacin (CIP) degradation as well as for water splitting using the photoelectrochemical path. The results illustrated that the degradation efficiency of the best photocatalyst, FeS/FeO@10 %2DTiO 2-x , was 90 % in the presence of PPS and 100 % in the case of H 2 O 2 , with rate constants equal to 12.1 × 10−3 min−1 and 17.6 × 10−3, respectively, at an optimized reaction condition of 100 ml of 20 ppm CIP, H 2 O 2 = 1.7 × 10−4 M, PPS = 1 × 10−3 M, catalyst = 0.1 g, pH = 3.5, t = 180 min, and at r.t. The exceptional activity of FeS/FeO@10 %2DTiO 2-x compared to other nanocomposites may be attributed to the efficient exciton separation via the Z-scheme transferring pathway and the continuous Fe2+ and Fe3+ shuttles that support the photoFenton activity. Numerous examinations, including those on toxicity, zero-point charge, total organic carbon, temperature and the suggested mechanism, are well evaluated and discussed. The FeS/FeO@4%TiO 2 black-C 3 N 4 photoelectrocatalyst exhibited excellent HER capacities in neutral medium, with overpotentials of −0.546 V at 10 mA cm−2 whereas for OER it shows overpotentials of 1.09 V mV at 10 mA cm−2. It showed 1.65 V of cell voltage at 10 mA cm−2, while maintaining 80 % stability. Interestingly, the latter electrode's high efficiency can be attributed to a variety of factors, including variations in spectral light absorption, a longer lifespan for photogenerated electron-hole pairs, a better charge transfer efficiency, and the integration of Ti3+ and O v generated from Ti-black with C 3 N 4. [ABSTRACT FROM AUTHOR]

[Display omitted] The oxide-based hybrid photocatalysts, especially TiO 2 -based, have attracted tremendous attentions because of their prominent photocatalytic performance. Currently, theoretical understandings on the relationship between the interface of TiO 2 -based heterostructures and their photocatalytic activity are still lacking. Here we systematically investigated the effects of interface structure on electronic properties of the g-C 3 N 4 /TiO 2 heterostructure using density functional theory (DFT) calculation. The interaction between monolayer g-C 3 N 4 and TiO 2 surface [with Anatase (1 0 1)/(0 0 1) facet] was explored, where a van der Waals heterojunction is formed. The presence of oxygen vacancy, nitrogen doping and hydrogen passivation on TiO 2 surface is found to dramatically alter the electronic properties of g-C 3 N 4 /TiO 2 heterostructure. Furthermore, the enhanced separation of electron − hole pairs and inhibited carrier recombination in the g-C 3 N 4 /TiO 2 interface was analyzed based on the Bader charge analysis and charge density difference. The theoretical analysis revealed that oxygen vacancy and hydrogen passivation on TiO 2 A001 surface induces the more significant charge separation, which may be the origin of enhanced photocatalytic efficiency of the g-C 3 N 4 /TiO 2 heterostructures. [ABSTRACT FROM AUTHOR]

In this study, the composite catalysts with the heterojunction between DUPG and BiOBr were used to degrade methyl orange (MO), and a g‐C3N4‐based ternary composite catalyst was developed. In our previous work, we prepared a D‐C3N4/U‐C3N4 isotype heterojunction with ordered mesoporous (DUPG) by co‐mixed calcination and hard template method. On this basis, we prepared DUPG/BiOBr nanoparticle uniformly distributed on DUPG nanosheets by coprecipitation self‐assembly method. The hybrids form a tightly coupled heterojunction that enhances the photoactivity and photostability of the DUPG/BiOBr composites. The results show that this tight coupling is beneficial, which facilitates the charge transfer between DUPG and BiOBr, thus promoting the effective separation of photogenerated electron hole pairs. Under visible light irradiation, the methyl orange conversion of the sample has higher photocatalytic reduction activity than BiOBr and DUPG, and its excellent photocatalytic activity is improved by light‐harvesting ability, increased specific surface area, active species and target pollution. [ABSTRACT FROM AUTHOR]

2D-g-C3N4 nanosheet was prepared and employed for the adsorption of elemental mercury (Hg0). The g-C3N4 was analyzed through X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR) methods, and the results showed that the prepared sample was well-defined 2D-nanosheet. The 2D-g-C3N4 sorbent exhibited a high Hg0 removal efficiency (> 90%) at the condition of temperature 120 °C. To investigate the mechanism of Hg0 adsorption on the 2D-g-C3N4 surface, corresponding theoretical exploration based on the first principle prediction and X-ray photoelectron spectroscopy (XPS) test was implemented. The DFT calculation results showed that Hg0 was strongly bound to the B1 site of the g-C3N4 surface with an adsorption energy change of -162.2 kJ mol−1, the equilibrium distance of Hg-C was 3.473 Å, and electron transfer between Hg and C atoms was 0.02. The results of XPS showed the main species of mercury was HgO on the surface of 2D-g-C3N4 sample and the interaction between C3N4 surface and Hg0 was physisorption. This study provides a demonstration of proof-of-concept demonstration that g-C3N4 is a promising sorbent capable of capturing Hg0, and presents in-depth understanding of Hg0 adsorption mechanism on 2D-g-C3N4 sorbent.

Graphitic carbon nitride (C 3 N 4) is the most widely reported member of the carbon nitride family because of its large pores which serve as alkali-metal atom storage sites. However, adsorption of Li atoms into these triangular pore sites occur at a high adsorption energy (E ad) of ∼4.2 eV which surpasses the desorption energy of bulk Li (3 eV) thereby resulting in ineffective desorption. Lithium storage in C 3 N 4 occurs via an intercalation/deintercalation process therefore the inability of adsorbed Li atoms to desorb from its structure results in structural instability, poor conductivity and limited reversible capacity. Here, we show that by doping Si atoms into the pore sites of C 3 N 4 , the Li E ad can be significantly decreased to 2.51 eV. This suitable E ad enabled effective Li transport, improved charge transfer, modulated the electronic conductivity, decreased the Li diffusion barrier and boosted the lithium storage capacity to 557.7 mAh/g. These results show that Si doping is an effective way to resolve the problems associated with C 3 N 4 and to achieve superior electronic properties and lithium storage capacity. These interesting results show the potential of Si doped C 3 N 4 for lithium ion batteries and this approach can be extended to other carbon nitride structures. [Display omitted] [ABSTRACT FROM AUTHOR]

The heavy-metal-free photocatalytic system, in which carbon nitride is coated on polylactic acid (PLA) as biodegradable plastic through a simple dip coating method, was used for dye decomposition under visible light irradiation. Solvent selection, solvent concentration, and the number of coatings for dip coating were investigated to optimize the conditions for loading carbon nitride on PLA. Carbon nitride cannot be coated on PLA in water, but it can be strongly coated by decomposing the surface of PLA with ethanol or chlorobenzene to promote physical adsorption and activate surface. The number of dip coatings also affected the photocatalytic decomposition ability. The photocatalytic system was able to decompose the dye continuously in the flow method, and dye (rhodamine B) was decomposed by about 50% at a residence time of 12 min (flow rate 0.350 mL/min) for 30 h. [ABSTRACT FROM AUTHOR]

Despite the conspicuous achievements in perovskite solar cells (PSCs), further improvement of the power conversion efficiency (PCE) is hindered by substantially detrimental carrier recombination resulting from the high interfacial charge defect density and inferior charge transport kinetics. Herein, an interface engineering strategy is developed to introduce a Lewis base thiophene or thiazole–modified C3N4 layer at the electron transfer layer (ETL)/perovskite interface to constitute a stepwise energy band alignment and passivate defects at interfaces of the perovskite film. Attributed to its well‐matched energy level with TiO2 and perovskite, the charge extraction efficiency and charge transfer dynamics can be promoted remarkably, greatly inhibiting charge recombination at the interface. Furthermore, thiophene and thiazole can donate the lone pair electrons in S or N atoms to undercoordinated Pb2+, which effectively passivates the electronic trap states caused by halogen vacancies, thereby greatly minimizing trap‐assisted nonradiative recombination in the PSCs. Eventually, the thiazole–C3N4/perovskite‐based devices acquire an outstanding efficiency of 19.23%, supported by an enhanced open‐circuit voltage (VOC) of 1.11 V with improved moisture stability. This work provides an avenue for interfacial energy level modulation and defect passivation strategies for a rational interface microstructure design for meliorating the performance of PSCs. [ABSTRACT FROM AUTHOR]

Establishing effective charge transfer channels between two semiconductors is key to improving photocatalytic activity. However, controlling hetero-structures in situ and designing binding modes pose significant challenges. Herein, hydrolytic SnCl 2 ·2H 2 O is selected as the metal source and loaded in situ onto a layered carbon nitriden supramolecular precursor. A composite photocatalyst, S 4 -Sn-N 2 , with electron pathways of SnS 2 and tubular carbon nitriden (TCN) is prepared through pyrolysis and vulcanization processes. The contact interface of SnS 2 -TCN is increased significantly, promoting the formation of S 4 -Sn-N 2 micro-structure in a Z-scheme charge transfer channel. This structure accelerates the separation and transport of photogenerated carriers, maintains the stronger redox ability, and improves the stability of SnS 2 in this series of heterojunctions. Therefore, the catalyst demonstrated exceptional photocatalytic hydrogen production efficiency, achieving a reaction rate of 86.4 µmol h -1 , which is 3.15 times greater than that of bare TCN., (© 2024 Wiley‐VCH GmbH.)

A set of C3N4 samples has been prepared by using melamine, cyanuric acid and barbituric acid as the precursors. The materials were subjected both to physical and chemical characterization and were used as photocatalysts for the selective oxidation of aromatic alcohols in water suspension under UV and visible irradiation. The photoactivity of the materials versus the partial oxidation of four substituted benzyl alcohols was investigated. The type and position of the substituents in the aromatic molecule influenced conversion and selectivity to the corresponding aldehyde. The presence of barbituric and cyanuric acids in the preparation method has changed the graphitic-C3N4 structure, and therefore both the characteristics of the material and the ability of light to activate the surface of the photocatalyst. The most active material prepared in the presence of melamine and cyanuric acid showed a remarkable selectivity towards the aldehyde even under visible irradiation. [ABSTRACT FROM AUTHOR]

X-ray photoelectron spectroscopy (XPS) was used to characterize a graphitic carbon nitride (g-C3N4) sample synthesized by the high temperature treatment of urea. Core-level C(1s) and N(1s) spectra are presented to aid fitting of such materials and address inconsistencies noted within published research literature. [ABSTRACT FROM AUTHOR]

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• The rational synthesis of homogeneously surface embedded cobalt clusters: g-C 3 N 4 system. • The cobalt clusters are successfully stabilized via NH 2 -bpy moieties. • Resulted photocatalyst was effective for the CO 2 reduction under sunlight irradiation. • Achieved very high rate of conversion (CO 2 to CO) and apparent quantum yield (3.2% at 420 nm). • A new one-step strategy to prepare metal clusters embedded photocatalysts. Metal clusters catalyst embedded in semiconductors is the key factor for an efficient photocatalyst toward photocatalytic CO 2 reduction. However, developing a simple method to synthesize such photocatalyst with these features has remained challenging. Herein, a rational one-step synthesis of cobalt clusters embedded in g-C 3 N 4 layers is developed for an enhanced photocatalytic CO 2 reduction. The tiny cobalt clusters are embedded into the g-C 3 N 4 structure and stabilized through the interaction with NH 2 -bpy moieties. Besides, the ligands of cobalt complex can copolymerize with urea during the synthesis owing to the presence of amino groups, thus providing a direct electron transfer between carbon nitride and cobalt clusters, which act as the light harvester and active reduction site, respectively. Consequently, a volcano relationship between the CO generation rate and the cobalt clusters incorporated into the carbon nitride matrix was found. Under optimized conditions, representative C 3 N 4 -0.5CoO x exhibits the very high CO generation rate of 2.6 μmol.h−1. Its apparent quantum yield of 3.2% at 420 nm and 1.0% at 460 nm, which is one of the highest values reported so far. The finding offers new opportunities for designing metal clusters catalysts toward photocatalytic CO 2 reduction based on the judicious use of the metal complex. [ABSTRACT FROM AUTHOR]

Developing photoanode with proficient sunlight harvesting, stability as well as enhancing the electron injection across the interface remains a major challenge in the photoelectrochemical water splitting strategy to generate hydrogen. Herein, we design and fabricate an organic/inorganic TiO 2 /C 3 N 4 /CNT photoanode by a hydrothermal technique which exhibits much enhanced photoelectrochemical properties. The TiO 2 /C 3 N 4 /CNT photoanode exhibits a photocurrent density of 2.94 mA/cm2, which is ~6.4 time higher than pristine graphitic carbon nitride (C 3 N 4) at an applied bias potential of 0.6 V vs. Ag/AgCl. The excellent photoelectrochemical performance benefits from the impactful migration of photo-induced electrons at the TiO 2 /C 3 N 4 interface from C 3 N 4 to TiO 2 and their intimate interface contact with CNT. Kelvin probe force microscopy result shows a smaller interface barrier height (~10 meV) between TiO 2 and C 3 N 4 , suggesting that electrons transport is favored through TiO 2 /C 3 N 4 interfaces in a ternary photoanode. The TiO 2 /C 3 N 4 /CNT photoanode exhibited an onset potential of 0.25 V vs. Ag/AgCl which is much lower compared to pristine C 3 N 4. The electrochemical impedance spectroscopy results also confirmed the enhanced electron injection across the interface in a ternary photoanode. These results demonstrate a promising approach to develop a highly proficient and visible light active photoanode with excellent stability for renewable energy applications. Image 1 • An Organic/Inorganic ternary photoanode was synthesized by the hydrothermal method. • KPFM results shows that electron transport is favored through TiO 2 /C 3 N 4 interfaces. • The ternary photoanode exhibits ~6.4 time higher photocurrent density than C 3 N 4. • The ternary photoanode exhibited excellent photostability. [ABSTRACT FROM AUTHOR]