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The photodegradation and deadhesion of mussel-inspired polydopamine was reported from nanoscale disassembly to effective mineralization. Various PDA coated templates and PDA hollow structures can be photodegraded by this strategy. The patterned and gradient surfaces were prepared by the "top-down" method under the control of light scope and intensity, respectively. [Display omitted] Mussel-inspired polydopamine (PDA) coating has been utilized extensively as versatile deposition strategies that can functionalize surfaces of virtually all substrates. However, the strong adhesion, stability and intermolecular interaction of PDA make it inefficient in certain applications. Herein, a green and efficient photocatalytic method was reported to remove adhesion and degrade PDA by using TiO 2 -H 2 O 2 as photocatalyst. The photodegradation process of the PDA spheres was first undergone nanoscale disassembly to form soluble PDA oligomers or well-dispersed nanoparticles. Most of the disassembled PDA can be photodegraded and finally mineralized to CO 2 and H 2 O. Various PDA coated templates and PDA hollow structures can be photodegraded by this strategy. Such process provides a practical strategy for constructing the patterned and gradient surfaces by the "top-down" method under the control of light scope and intensity. This sequential degradation strategy is beneficial to achieve the decomposition of highly crosslinked polymers. [ABSTRACT FROM AUTHOR]

Graphite-phase carbon nitride (g-C 3 N 4) is widely recognized as a remarkable material for both the photocatalytic degradation of organic pollutants and photocatalytic water splitting for hydrogen production. In this study, we reported a method to obtain a broken hollow carbon nitride with nitrogen defects and hydroxyl groups, prepared from melamine and cyanuric acid through self-assembly. It demonstrated outstanding photocatalytic performance, achieving a 99.35% removal of Rhodamine B, 88.08% degradation of tetracycline hydrochloride, and a hydrogen production rate of 1671.12 μmol g−1 h−1, all of which are superior to the performance of bulk g-C 3 N 4. The superior redox performance was attributed to the significant increase in specific surface area and the synergistic effects of nitrogen defects and hydroxyl groups. These modifications effectively altered the built-in electric field, electronic structure, and redox potential of g-C 3 N 4. Experimental and theoretical analyses revealed that photogenerated electrons were enriched in nitrogen vacancies, while holes were captured by hydroxyl groups, resulting in the rapid transfer and separation of charge carriers. On this basis, possible synthesis pathways and photocatalytic mechanisms of the catalyst were proposed. This work provides a promising method for preparing modified carbon nitride with excellent photocatalytic performance. [Display omitted] • V N -CN-OH-45 shows a unique broken hollow tubular structure. • Nitrogen defects and hydroxyl groups synergistically enhance redox capacity. • DFT calculations indicate that defects facilitate charge separation and transfer. • Exceptional photocatalytic degradation of RhB and TCH. • Outstanding photocatalytic hydrogen production performance. [ABSTRACT FROM AUTHOR]

For heterojunction system, the lack of stable interfacial driving force and definite charge transfer channel makes the charge separation and transfer efficiency unsatisfactory. The photoreaction mechanism occurring at the interface also receives less attention. Herein, a 2D/2D Z‐scheme junction BiOBr@NiFe‐LDH with large‐area contact featured by short interface hydrogen bonds and strong interfacial electric field (IEF) is synthesized, and in situ photoinduced metallic species assisting charge transfer mechanism is demonstrated. The hydrogen bonds between O atoms from BiOBr and H atoms from NiFe‐LDH induce a significant interfacial charge redistribution, establishing a robust IEF. Notably, during photocatalytic reaction, Bi0 and Ni0 are in situ performed in heterojunction, which separately act as electron transport mediator and electron trap to further accelerate charge transfer efficiency up to 71.2 %. Theoretical calculations further demonstrate that the existence of Bi0 strengthens the IEF. Therefore, high‐speed spatial charge separation is realized in Bi0/BiOBr@Ni0/NiFe‐LDH, leading to a prominent photocatalytic activity with a tetracycline removal ratio of 88.3 % within 7 min under visible‐light irradiation and the presence of persulfate, far exceeding majority of photocatalysts reported previously. This study provides valid insights for designing hydrogen bonding heterojunction systems, and advances mechanistic understanding on in situ photoreaction at interfaces. [ABSTRACT FROM AUTHOR]

In this study, a novel Z-scheme heterojunction based on g-C3N4/TiO2/NiCo2O4 nanocomposite was synthesized using a combination of hydrothermal and ultrasonic methods and investigated the photocatalytic degradation of Rhodamine B (RhB) dye. The synthesized nanocomposite was characterized XRD, FT-IR, FE-SEM, TEM, EDS, PL, UV–Vis DRS techniques. Subsequently, various parameters such as the effect of NiCo2O4 amount in the composite structure, pH, initial pollutant concentration, photocatalyst dosage, and different scavengers were investigated to determine the exact mechanism of the photocatalytic process. In different concentrations of NiCo2O4, the base value (X: 1) was determined as the optimal value in photocatalytic degradation. g-C3N4/TiO2/NiCo2O4 composite had the highest percentage of 99.5% Rh.B dye degradation in 60 min. In addition, by examining the pH, it was found that its optimal value is 7, and the rate of dye degradation in this condition is more than other materials, and the rate constant value is 0.069 min–1. In addition, the g-C3N4/TiO2/NiCo2O4 catalyst showed good performance for each reuse and retained about 82% of its initial photocatalytic activity after 5 cycles. The results indicate that photoinducd (RhB) holes play a crucial role in the photocatalytic degradation of RhB in the presence of the g-C3N4/TiO2/NiCo2O4 nanocomposite via pair Z-scheme system. In the Z-scheme system, the rapid recombination between the hole-electron pair is not observed due to the electron trapping effect of the needle-shaped NiCo2O4 structure, resulting in high photocatalytic efficiency and dye degradation. Therefore, Z-scheme systems are efficient and effective for the removal of water pollutants. [ABSTRACT FROM AUTHOR]

This study investigates the synthesis, characterization, and application of ZnO/SnO2 nanocomposite (ZnO/SnO2 NC), focusing on their photocatalytic and antioxidant properties. The sol-gel technique was utilized for the synthesis of the ZnO/SnO2 NC. Subsequent characterization was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and UV-visible (UV-Vis) spectrophotometry. The XRD analysis indicated crystallite dimensions of 15 nm for ZnO/SnO2 and 21 nm for pure ZnO NPs. The photocatalytic efficiency was assessed by the degradation of Toluidine Blue (TB) and m-Toluidine Blue (m-TB) dyes. The ZnO/SnO2 NC demonstrated degradation rates of 99% for both TB and m-TB within 120 and 140 min of sunlight exposure, respectively. Furthermore, the scavenging activity of superoxide radicals was evaluated, with the ZnO/SnO2 NC exhibiting an Half-maximal inhibitory concentration (IC50) value of 48.12 µg∙mL− 1, compared to 60.03 µg∙mL− 1 for pure ZnO. This research highlights the potential of ZnO/SnO2 NC in environmental remediation and biomedical applications. [ABSTRACT FROM AUTHOR]

Tetracycline hydrochloride (TCN), widely recognized for its broad-spectrum efficacy and cost-effectiveness as an antibiotic, has raised significant environmental and health concerns due to its contamination in water bodies. This study introduces an innovative approach to address this issue by employing a titanium dioxide/graphitic carbon nitride (TiO2/g-C3N5) nanocomposite through photocatalysis. The synthesis of this composite involved a hydrothermal method, and a comprehensive characterization was conducted using XRD, FT-IR, and SEM techniques. The formed heterojunction between TiO2 and g-C3N5 exhibited remarkable photocatalytic degradation capabilities, achieving a removal rate of over 85 % within a short period of 135 min. This signifies the composite's efficiency in breaking down TCN in aqueous environments. Beyond its high effectiveness, the TiO2/g-C3N5 nanocomposite presents itself as an environmentally friendly and sustainable solution for addressing the critical issues associated with antibiotic contamination in water. This study underscores the potential of photocatalysis using TiO2/g-C3N5 as a promising technology for mitigating the adverse effects of TCN on both ecosystems and human health. [ABSTRACT FROM AUTHOR]

In this study, MXene nanosheets were utilized as a co-catalyst to modify the graphitic carbon nitride photocatalyst and synthesize the g-C3N4/MXene composite. Eosin Y dye was employed as a model organic pollutant to evaluate the photocatalytic degradation performance. Eosin Y, an anionic dye, poses significant environmental and health risks due to its resistance to biodegradation, as well as its toxicity and carcinogenicity. To synthesize this composite, graphitic carbon nitride was initially produced using a simple thermal polymerization method. Subsequently, it was protonated and assembled with MXene nanosheets through a self-assembly process. The MXene nanosheets were synthesized using a Mild method. Characterization and confirmation of the successful synthesis of the g-C3N4/MXene composite were conducted through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDS) analyses. The results of the Eosin Y degradation experiments indicated that the composite with a 7% weight ratio of MXene nanosheets exhibited the highest photocatalytic performance among the various weight ratios tested. The incorporation of MXene nanosheets more than doubled the photocatalytic degradation efficiency of graphitic carbon nitride. The MCN7 sample was able to remove 98% of 25 mg/L Eosin Y dye from an aqueous solution within 120 minutes, using a photocatalyst dosage of 0.4 g/L. The findings of this study demonstrate that the integration of MXene nanosheets with graphitic carbon nitride significantly enhances the photocatalytic performance of graphitic carbon nitride in the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

This study aimed to create composite nonwoven fabric from polylactic acid (PLA) and nano-silver coated titanium dioxide (Ag/TiO2) for the degradation of carbaryl insecticide in water under UV irradiation. The obtained composite nonwoven exhibited a yellow-gold color and similar thermal and physical characteristics, including fiber size and a narrow size distribution, to the PLA nonwoven. Furthermore, it exhibited superior mechanical properties compared to the PLA nonwoven, particularly in terms of breaking strength. Among the composite nonwovens, the one with the masterbatch added at 10 phr (PLA-2) demonstrated the highest breaking strength. Additionally, it was noteworthy that all ratios of the composite nonwoven displayed excellent carbaryl insecticide decomposition efficiency under UV light, consistently achieving around 40% degradation. Furthermore, these composite nonwovens proved reusable for up to three cycles without a loss in efficiency. These findings suggest that composite nonwovens made from nano-silver coated titanium dioxide photocatalysts and biodegradable polylactic acid hold promise as alternative materials for the decomposition of carbaryl insecticide in natural water sources. [ABSTRACT FROM AUTHOR]

In this present work, photocatalysts based on a new pyrochlore-type solid solution were prepared using the ceramic method at 1000°C. X-ray diffraction (XRD) analysis shows the existence of a solid solution with pyrochlore structure Bi1.5Sb1.5Zn1–xCuxO7 (0 ≤ x ≤ 1). Scanning Electron Microscope (SEM) images exhibited a slight difference in the external morphology of the samples. The UV-diffuse measurement revealed a change in the absorbance from the UV part for the zinc-rich compound to the visible part for the copper-rich compound. The Energy band gap values were between 3.15 and 1.84 eV. The photocatalytic activity of these prepared mixed oxides was studied for the photo-degradation of the dye Orange II (ORII) as an organic pollutant, in the presence of hydrogen peroxide (H2O2) as an oxidising agent, under sunlight irradiation, by varying different parameters such as the catalysts mass, the oxidant volume, the concentration of the pollutant and the pH. The experimental results obtained by UV-visible spectroscopy revealed that the removal efficiency of ORII increased with increasing the irradiation time for all tested photocatalysts. The pseudo-first-order kinetic model gave the best fit, with the highest correlation coefficients (R2 = 0.99). The results of this study revealed the potential and various advantages of these new efficient photocatalysts. [ABSTRACT FROM AUTHOR]

The present study uses Adenanthera pavonina L. plant extract to synthesize Y/Fe2O3 nanoparticles in a sustainable and efficient manner. Several physicochemical investigations were performed on the synthesized Y/Fe2O3 to evaluate its structure and morphological characteristics. The high crystallinity of Fe2O3 and decreased crystal size of Y/Fe2O3 were revealed by the XRD study. The formulated Y/Fe2O3 was spherical in shape. Y/Fe2O3 has shown potential photocatalytic activity in the degradation of congo red and brilliant green dyes in the presence of visible light. Degradation efficiency is higher than 90% for both dyes. In addition, the antibacterial activity of Y/Fe2O3 was measured against pathogenic strains of Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Micrococcus luteus, Proteus mirabilis, Pseudomonas putida, Shigella dysenteriae, and Staphylococcus aureus. Y/Fe2O3 showed promising antibacterial activity against all microorganisms. Micrococcus luteus showed a higher zone of inhibition (equal to 35 mm in diameter) than other microorganisms using Y/Fe2O3. Thus, it is established that the green synthesized Y/Fe2O3 nanoparticles are active catalysts for the photocatalytic degradation of hazardous dyes and have antibacterial properties against different bacterial stains. [ABSTRACT FROM AUTHOR]

With increasingly serious environmental pollution problems, the development of efficient photocatalytic materials has become a hotspot in current research. This study focused on phosphorus-doped carbon nitride/titanium dioxide (PCT) Z-type heterojunctions, aiming to deeply investigate their photocatalytic degradation and photosensitive antimicrobial properties. A PCT Z-type heterojunction was successfully fabricated using melamine phosphate, cyanuric acid, and titanium dioxide. The structure, morphology, and optical properties of PCT Z-type heterojunctions were explored by FTIR, XRD, XPS, BET, SEM, UV-Vis DRS, TEM, EIS, and PL. A comprehensive and in-depth analysis of the structure, morphology, and optical properties of PCT Z-type heterojunctions was carried out. The photocatalytic degradation experiments revealed that PC3T Z-type heterojunctions exhibited an excellent degradation capability for methylene blue (MB) under visible light. The effect of PC3T on the adsorption–photocatalytic degradation of MB is more than 1.5 times that of a single titanium dioxide and P-doped carbon nitride. In the photosensitive antimicrobial performance study, PC3T reduced the survival rate of E. coli to 7%, after 120 min. Through free radical trapping experiments, it was shown that the hydroxyl radicals and superoxide radicals exerted an influence on the photocatalytic process. This study offers new ideas and approaches to address environmental pollution problems and holds significant theoretical and applied value. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, Ag2CrO4@NiFe-LDH nanoparticles were synthesized by hydrothermal method for photocatalytic degradation of Alizarin Red (AR) dye. Three composites with different molar percentages were prepared, among which 50%Ag2CrO4@50%NiFe-LDH composite was the best sample with a removal rate of 97.1% in AR degradation. Also, the properties, structure, and characteristics of pure Ag2CrO4 and NiFe-LDH and their composites were determined by XRD, FESEM, FTIR, EDX mapping, and UV–visible analyses. It was found that Ag2CrO4@NiFe-LDH composites with the formation of heterogeneous structure of Z-scheme, in addition to increasing the active sites and increasing the specific surface, decrease the recombination rate of pure Ag2CrO4 and NiFe-LDH. Also, the Box–Behnken design technique, which is one of the most common designs used in response surface methodology, was used to optimize the operating conditions and investigate the effect of 4 independent parameters: catalyst amount, solution concentration, pH, and light intensity. The importance of independent parameters and their interactions were determined by ANOVA. By means of numerical optimization, the optimal values of the selected parameters equal to 1.34 g/L of catalyst, concentration of 16.45 mg/L, pH = 10.74, and light intensity of 15.53 W were obtained as optimal conditions with a desirability coefficient of 1.00 and an absorption value of 89.34%. The closeness of adjusted R2 (0.9838) and predicted R2 (0.9507) values show that this model can be successfully used for prediction. [ABSTRACT FROM AUTHOR]

For the first time, a novel catalyst named Dy2EuSbO7 was successfully synthesized via the high-temperature solid-state sintering method (HTSSM). Dy2EuSbO7/ZnBiDyO4 heterojunction photocatalyst (DZHP) was fabricated through the HTSSM for degrading chlorpyrifos (CPS) in the pesticide wastewater under visible light irradiation (VSLID). Under VSLID, DZHP could effectively degrade CPS in pesticide wastewater. The experimental outcomes suggested that the kinetic curve with the Dy2EuSbO7/ZnBiDyO4 heterojunction (DZH) as a photocatalyst for the reduction of CPS under VSLID conformed to the first-order kinetics (FOKT). After VSLID of 156 min, the photocatalytic degradation (PTD) removal rate of CPS using DZH as photocatalyst was 1.12 times, 1.21 times, or 2.96 times that using Dy2EuSbO7 as a photocatalyst, ZnBiDyO4 as a photocatalyst, or nitrogen-doped titanium dioxide as a photocatalyst. After VSLID of 156 min for four cycle degradation tests (FCDTS) with DZH as a photocatalyst, the removal rate of CPS reached 98.78%, 97.66%, 96.59%, and 95.69%, respectively. Above results indicated that the DZHP possessed high stability. Experiments with the addition of trapping agents showed that hydroxyl radicals (•OH) owned the strongest oxidative removal ability for degrading CPS compared with superoxide anions (•O2−) or holes (h+). The oxidation capacity of three oxidation radicals for eliminating CPS was ranked in the ascending order as follows: h+ < •OH < •O2−. Lastly, the possible degradation pathway and degradation mechanism of CPS were discussed in detail. A visible light responsive heterojunction catalyst with high catalytic activity and a photocatalytic reaction system which were capable of efficiently removing toxic organic pollutants from pesticide wastewater were obtained. [ABSTRACT FROM AUTHOR]

Utilising the solution combustion technique, nanocrystalline photocatalysts that included both pristine TiO2 and doped TiO2 with various La (III) dopant percentages (1, 3, 5, and 7 mol%) were created. Different methods, including thermal analysis, high resolution-transmission electron microscopy (HR-TEM), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FT-IR), and field-emission scanning electron microscopy (FE-SEM), were used to investigate the prepared nanostructures. The XRD results indicated the anatase form and the crystalline nature of the products (pristine and doped TiO2) in the size range of a crystallite (5–16.5) nm. The photocatalytic assessment of the prepared nano-photocatalysts was carried out by crystal violet (CV) decolourisation under ultraviolet (UV) light. The findings revealed that 3% La-TiO2 showed the highest degradation efficiency (95.98%) in 70 min with a pseudo-first-rate constant of k = 4.73 × 10−2 min−1, compared to pristine TiO2 and the other TiO2 nanostructures with various La (III) dopant ratios. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the performance of the Pd@TMU-16 to act as a photocatalyst in degrading the Acid Red 88 (AR88) dye from an aqueous solution, via photocatalysis process, using UV irradiation. The synthesis of this catalyst was performed under conditions of thermal solvent and its characteristic parameters were confirmed using the XRD, Band gap, SEM, BET, pHPCZ, and FTIR methodologies. The influence exerted by the operative parameters on the AR88 degradation, which included the pH, reaction time, radiation intensity, catalyst mass, and initial dye concentration was examined. At the optimum condition of photocatalysis and utilising only 0.75 g of Pd@TMU-16, total degradation of 10 mg/L dye concentration was performed. From the kinetic studies, the dye degradation indicated that it was similar to the pseudo-first-order model, and the dye degradation mechanism had taken place through the hydroxyl (•OH) and superoxide radicals (•O⁻₂). The adsorbent reusability was also studied, and from the results it was evident that the 18% decrease observed after six consecutive cycles of catalyst use, clearly indicated its stability. For radiation intensities of 8, 15, 24, and 36 W, the Energy Consumed per m3 of the treated wastewater was found 20.2, 28.8, 34.1, and 36.9 kWh, respectively. From these results, namely the low energy gap (2.3 eV) and high degradation capacity, it was evident that the Pd@TMU-16 can be useful, under UV light, as a powerful catalyst in the elimination of dyes and other organic contaminants from polluted aqueous media. [ABSTRACT FROM AUTHOR]

In this study, a novel photocatalyst comprising graphitic carbon nitride (g-C3N4) and tungsten oxide (WO3) in different weight ratios was fabricated through a facile synthesis method. The synthesized nanocomposites were characterized using various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–vis spectroscopy to elucidate their structural and optical properties. The photocatalytic performance of the g-C3N4/WO3 nanocomposite was evaluated for Rhodamine (RhB) degradation under visible light irradiation. Remarkably, the 3 wt % g-C3N4/WO3 nanocomposite exhibited a superior degradation efficiency of 96% (rate constant ~ 0.02714 min−1) compared to pure g-C3N4 and WO3. The major role was played by both holes (h+) and superoxide anion radicals (•O2−) in the degradation process. This performance is attributed to the synergistic effect between the two components, which facilitated efficient charge separation leading to decreased recombination of photo-generated electron–hole pairs, and improved light absorption. Additionally, the optimized nanocomposite was employed for electrochemical detection of 2-nitrophenol (2-NP), showcasing remarkable sensitivity (limit of detection ~ 0.22 µM) and selectivity towards 2-NP. This positions it as a promising candidate for environmental monitoring applications. In summary, this study underscores the potential of the g-C3N4/WO3 nanocomposite in wastewater treatment as a visible light photocatalyst, alongside its utility in electrochemical sensing of organic pollutants. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Nanchang University (Engineering & Technology) is the property of Nanchang University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates the effect of iron-modified nano-TiO2, using the co-precipitation method with different concentrations of FeCl3 (0.1, 1, and 10%), to improve its photocatalytic properties for outdoor applications. To this end, modified and unmodified nano-TiO2 were characterized using different techniques. The optical properties were characterized by diffuse reflectance spectroscopy (DRS) followed by band gap calculation. X-ray diffraction (XRD) was used to analyze the crystalline structure. Chemical and morphological characterization were carried out using energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM). The photocatalytic activity was investigated by decolorizing Rhodamine B aqueous solutions under similar sunlight irradiation. The results indicate that the modification improved light absorption in the UV range for all iron concentrations; however, only the concentration of TiO2: FeCl3 (10%) shifted the absorption to the visible region. Also, including Fe3⁺ in TiO2 decreased the band gap energy from 3.14 to up to 2.80 eV. There were variations in crystallite size from 21.13 to up to 40.07 nm. The nano-TiO2 morphology analysis showed that it did not change after iron modification. EDS showed an FeCl3 peak only at higher concentrations (10%). In addition, the 0.1% Fe-modified TiO2 exhibited the highest activity in the photocatalytic process, with an efficiency of 95.23% after 3 h of irradiation. [ABSTRACT FROM AUTHOR]

Herein, this study has examined the influence of Zn2+ sources during a biogenic-mediated pathway to synthesize ZnO nanoparticles with highly desirable solar-responsive catalytic properties. Salts of nitrate, acetate and chloride have been utilized. The ZnO powders underwent characterization using diverse analytical tools, including XRD, FTIR, Raman, BET, SEM, TEM with EDS/elemental mapping and UV-vis absorption/emission spectroscopic analyses. Accordingly, precursors have proved to affect crystallinity, morphology, surface characteristics, optical properties and the photocatalytic degradation of methylene blue (MB) model pollutant. It was observed that ZnO derived from zinc acetate precursor (Z-AC NPs) exhibits very fast photocatalytic degradation of MB at pH 11 with superior kinetic estimates of 0.314 min−1 and t1/2 = 2.2 min over many of recent reports. In contrast, the chloride precursor is not recommended along with the employed biogenic route. The intriguing findings could be directly correlated to the decreased crystal size, augmented surface area, the hexagonal morphology of the crystals, high potency in absorbing visible photons, high efficacy in separating photogenerated charge carriers and producing high amounts of •OH radicals. Further testing of Z-AC NPs in photocatalytic remediation of water samples from Dumat Aljandal Lake in Aljouf, Saudi Arabia, contaminated with MB and pyronine Y (PY) dyestuffs, showed high dye photodegradation. Therefore, this work could lead to an extremely fast avenue for decontaminating wastewater from hazmat dyestuff. [ABSTRACT FROM AUTHOR]

Organic dyes are stable and persistent toxic compounds in the aquatic environment that are refractory to decompose by removal methods such as physico-chemical, optical and biological. Their presence in the aquatic media threatens human and wildlife. Herein, ZnO nanoparticles (NPs) due to good chemical durability, low cost and good photocatalytic performance was anchored on biochar (ZnO@biochar) nanocomposites were synthesized towards activation of peroxymonosulfate (PMS) for the photocatalytic removal of methyl orange (MO) dye. Several methods were used to characterization of the nanocomposites including FESEM, XRD, PL, EDS, FT-IR spectroscopy, and N2 adsorption/desorption. The results of the techniques demonstrated that the well-dispersed ZnO NPs were loaded onto the biochar surface. According to the particle size distribution graph, the average particle size of 64 nm was obtained for the ZnO NPs. BET analyzes showed that pore volume, the specific surface area (SSA) and average pore size of the synthesized nanocomposite increased. The survey of effective operational parameters indicated that the highest photocatalytic activity for MO removal was in the pH 3 of solution, 5 ppm initial dye concentration, 30 mg ZnO/biochar nanocomposite, and 20 mg PMS dose under LED-50W lamp irradiation (97.03% in the reaction time of 80 min). During the process, the reduction of the total organic carbon (TOC) contents and chemical oxygen demand (COD) were observed. Moreover, the MO degradation kinetics under optimal operating conditions were determined. It is concluded that the ZnO@biochar nanocomposite/PMS process was an efficient degradation method for the decomposition of the dye pollutant. [ABSTRACT FROM AUTHOR]

The dyeing process in textile industries has significant environment implication, primarily due to the release of a large amount of water effluents. Photocatalyst is a perennially effective technique used for the degradation of toxic, low- biodegradable hazardous effluents from water bodies. This method is highly selective, cost-effective, straightforward synthesis, and environmentally friendly process. Semiconductor metal oxides-based photocatalysts have gained attraction due to their superior properties including less toxicity and environment applications. However, their widespread implementation has diminished because of the poor photocatalytic activity in the visible region. To address this limitation, incorporating a conducting polymer particularly Polyaniline, has proven more effective. The enhanced charge-carrying capacity and ability to change the optical band gap makes the semiconductor more efficient for the degrading the organic effluents from the water bodies. This review primarily focuses on degradation of poisonous dyes present in textiles wastewater, using the polyaniline-semiconductor nanocomposite as a photocatalyst material. [ABSTRACT FROM AUTHOR]

In recent years, environmental pollutants have become more hazardous to both human health and eco-systems. One potential method for cleaning up the environment is eco-friendly semiconductor photocatalysis. There are several types of mechanism associated with semiconductor photocatalysis, in that, Step-scheme (S-scheme) photocatalysis (SSPC)grabbed plenty of interest in the domain of developing and transforming solar fuel due to their effective charge spatial separation and robust redox capabilities. Herein, this article highlights and summarizes the most recent advancements in S-scheme heterojunctions photocatalysis (SSHJPC); also, briefly encapsulate the process, reaction principle, Mechanism, Synthesis strategies, Frontier characterization techniques and their applications in solar energy conversion. Finally, conclusions are drawn and future prospects for solar energy conversion issues are presented. [ABSTRACT FROM AUTHOR]

Wastewater containing phenolic organic compounds, such as phenol, produced during industrial manufacturing processes, poses a significant threat to aquatic ecosystems and crops. Photocatalytic technology is considered the most promising approach to water treatment due to its efficiency and eco-friendly advantages. Compared to other photocatalysts, Bi-based oxides are more efficient due to their unique layered structure, which allows for photocatalytic reactions to occur between layers. This review introduces the synthesis methods of various bismuth-based multi-element oxides and their efficiency in the photocatalytic decomposition of phenol. The effects of elemental doping, defect introduction, and heterojunction construction on the catalytic performance and structure of Bi-based oxides are discussed. The mechanisms for the photocatalytic degradation of phenol over different materials are also summarized and discussed. [ABSTRACT FROM AUTHOR]

The synthesis of high‐efficiency magnetic composite photocatalyst by doping magnetic cobalt ferrite and compounding single semiconductor photocatalyst is a promising strategy to improve the oxidation ability of photocatalytic systems. In this paper, CoFe1.95Dy0.05O4 (CFDO) was prepared by doping Dy element into magnetic CoFe2O4, and Ag2S (AS)/CFDO with high‐efficiency magnetic photocatalyst was synthesized by compounding AS with CFDO as the substrate. The photocatalytic samples were characterized by different advanced characterization methods, and their photocatalytic degradation of methylene blue (MB) was studied. The results show that AS/CFDO exhibits higher visible light response, excellent photogenerated charge separation ability and migration efficiency, and excellent catalytic performance in the catalytic degradation system. The photocatalytic activity of AS/CFDO was the highest, and its photocatalytic degradation kinetic constant K was 2.48 and 1.54 times that of AS and CFDO, respectively. In addition, the catalyst contained in the catalytically contaminated solution can be effectively separated by an external magnetic field to achieve multiple cycles of degradation and recycling. The cyclic degradation experiments showed that AS/CFDO exhibited high degradation stability during the photodegradation process. After the fifth reuse, the degradation efficiency was still more than 88.0%. Finally, the possible photocatalytic mechanism of the samples was discussed. Therefore, this work provides an effective solution for the construction of photocatalysts with high efficiency, magnetic recovery, and cyclic degradation stability and avoids the secondary pollution of catalysts to organic wastewater. It is of great significance to create an environmentally friendly catalytic method for efficient cyclic degradation of organic wastewater. [ABSTRACT FROM AUTHOR]

Cerium‐doped zinc oxide (Ce‐ZnO) nanocones with cerium concentrations of 0, 0.5, 1, and 2 % were synthesized using a sol‐gel method. Their effectiveness as photocatalysts for degrading dyes such as Rhodamine B (RhB), Methylene Orange (MO), and Methylene Violet (MV) was evaluated. The optical and structural properties, particle size distribution, and morphology of these nanocones were examined using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet‐visible (UV‐Vis) spectrophotometry. XRD results confirmed that the nanocones were highly crystalline with a hexagonal wurtzite structure, and a noticeable blue shift was observed in the Ce‐doped ZnO nanocones compared to pure ZnO. The photocatalytic performance under UV exposure showed that cerium doping significantly improved the degradation of RhB, MO, and MV. Notably, ZnO nanocones doped with 1 % cerium exhibited the highest photocatalytic efficiency, achieving 100 % degradation of RhB within 60 minutes. Additionally, 1 % Ce‐ZnO nanocones demonstrated degradation efficiencies of 86.3 % for MO and 74.9 % for MV within the same time frame. [ABSTRACT FROM AUTHOR]

This study focuses on enhancing the properties of kaolin (Kao) clay by incorporating Zinc oxide nanoparticles (ZnO NPs) and further functionalizing with agar biopolymer, resulting in the formation of Agar/Kao@ZnO nanocomposite (NC). The synthesized material underwent comprehensive composition, structure, surface, and optical properties analysis to confirm the formation. The material was evaluated as a photocatalyst for the degradation of 2,4‐dinitrophenol (DNP) under visible light irradiation. The optimized conditions for the photocatalytic degradation of DNP were determined as irradiation time 50 minutes, pH 4, catalyst dose 20 mg, and DNP concentration of 25 mg L−1, resulting in degradation efficiency of 99.63%. Trapping experiment validated the significant role of hydroxyl (•OH) radicals as reactive oxidant species (ROS) in the degradation of DNP in the presence of visible light. Through four consecutive cycles of reusability experiments, it was confirmed that the synthesized material is highly stable and efficient for DNP degradation. [ABSTRACT FROM AUTHOR]

Hybrid material of surgical mask activated carbon (SMAC) and Fe2O3 (SMAC-Fe2O3) composite was prepared by simple co-precipitation method and used as potential material for the remediation of 2,4-dicholrophenol (2,4-DCP). The XRD patterns exhibited the presence of SMAC and Fe2O3, FTIR spectrum showed the FeO-carbon stretching at the wavenumber from 400 to 550 cm−1. UV–Vis DRS results showed the band gap was 1.97 eV and 2.05 eV for SMAC-Fe2O3 and Fe2O3, respectively. The SEM images revealed that the Fe2O3 doped onto the fiber morphology of SMAC. The outcomes of the BET examination exhibited a surface area of 195 m2/g and a pore volume of 0.2062 cm3/g for the SMAC/Fe2O3 composite. The batch mode study shows the maximum adsorption and photocatalytic degradation efficacies which were 97% and 78%, respectively. The experimental data was studied with both linear and nonlinear adsorption isotherm and kinetics models. The nonlinear Langmuir isotherm and pseudo-second-order kinetics (PSOK) models have well fit compared with other models. The Langmuir maximum adsorption capacity (qmax) was found 161.60 mg/g. Thermodynamic analysis shows that the 2,4-DCP adsorption onto SMAC-Fe2O3 was a spontaneous and exothermic process. The PSOK assumes that the adsorption process was chemisorption. The photocatalytic degradation rate constant of 2,4-DCP was calculated using pseudo-first-order kinetics (PFOK) and the rate constant for SMAC-Fe2O3 and Fe2O3 were 0.859 × 10−2 min−1 and 0.616 × 10−2 min−1, correspondingly. In addition, the obtained composite exhibited good reusability after a few cycles. These results confirmed that SMAC-Fe2O3 composite is an effective adsorbent and photocatalyst for removing 2,4-DCP pollutants. [ABSTRACT FROM AUTHOR]

Ag3PO4/g-C3N4 photocatalytic composites were synthesized via calcination and hydrothermal synthesis for the degradation of rhodamine B (RhB) in wastewater, and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and diffuse reflectance spectroscopy (DRS). The degradation of RhB by Ag3PO4/g-C3N4 composites was investigated to evaluate their photocatalytic performance and cyclic degradation stability. The experimental results showed that the composites demonstrated notable photocatalytic activity and stability during degradation. Their high degradation efficiency is attributed to the Z-scheme transfer mechanism, in which the electrons in the Ag3PO4 conduction band and the holes in the g-C3N4 valence band are annihilated by heterojunction recombination, which greatly limits the recombination of photogenerated electrons and holes in the catalyst and enhances the activity of the composite photocatalyst. In addition, measurements of photocurrent (PC) and electrochemical impedance spectroscopy (EIS) confirmed that the efficient charge separation of photo-generated charges stemmed from strong interactions at the close contact interface. Finally, the mechanism for catalytic enhancement in the composite photocatalysts was proposed based on hole and radical trapping experiments, electron paramagnetic resonance (EPR) analysis, and work function evaluation. [ABSTRACT FROM AUTHOR]

In this study, we used an environmentally friendly green fuel combustion synthesis method to create Cu 3 Bi 3 S 7 (CBS) nanoparticles (NPs). A thorough characterization was carried out, including XRD, UV spectroscopy, SEM, TEM, PL spectroscopy, zeta potential analysis, BET Spectra and XPS Spectra. The formation of single-phase CBS NPs with average diameters of 50 nm was unequivocally confirmed by XRD analysis. UV spectroscopy revealed that the NPs absorbed significant visible light, highlighting their potential for use in photocatalytic degradation processes. The images from SEM and TEM clearly showed NPs with uniform size distribution and spherical morphology. The CBSNPs' defect state presence may be determined from the PL spectra. CBS NPs were particularly effective in photo-catalyzing the degradation of the indigo carmine (IC) dye when exposed to Uv light. Additionally, during an electrochemical sensing examination, the NPs demonstrated extraordinary sensitivity to glucose. Overall, our results highlight the tremendous potential for CBS NPs produced using ecologically friendly green fuel combustion synthesis to advance photocatalytic degradation and electrochemical sensing applications. • Cu 3 Bi 3 S 7 NPs synthesized by introducing a new green fuel combustion process. • Advanced techniques in the characterization of the NPs including detailed characterization. • Synthesis and evaluation of Cu 3 Bi 3 S 7 NPs for efficient photodegradation of dyes. • Electrochemical sensing applications investigation with focus on suitability for sensors construct. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) and graphitic carbon nitride (g‐C3N4) heterojunctions were prepared through the hydrothermal method and the calcination method (namely, MoS2/g‐C3N4‐1 and MoS2/g‐C3N4‐2) for the photocatalytic degradation of Rhodamine B. X‐ray diffraction and scanning electron microscopy confirmed the formation of a heterostructure composite between MoS2 and g‐C3N4. The bandgap of MoS2 and g‐C3N4 was studied with ultraviolet–visible diffuse reflection spectroscopy and electrochemical Mott‐Schottky tests. MoS2/g‐C3N4‐1 exhibits remarkable efficiency in degrading Rhodamine B, achieving 91.2 % degradation in 1 h, which is 1.06 times higher than MoS2/g‐C3N4‐2. Additionally, the MoS2/g‐C3N4‐1 heterojunction demonstrates good reusability, maintaining a degradation efficiency of 71.2 % after 5 cycles. The reason lies in that the MoS2/g‐C3N4‐1 possesses a larger specific surface area (33.078 m2g−1) than MoS2/g‐C3N4‐2 (28.621 m2g−1). Free radical quenching experiments indicate that ⋅O2− serves as the primary active species for photocatalytic degradation. The findings indicate that incorporating g‐C3N4 into MoS2 improves its photocatalytic capability due to aligned energy bands, promoting charge transfer, and reducing electron‐hole recombination. [ABSTRACT FROM AUTHOR]

TiO2 photocatalysis has gained attention as a cost‐effective way of degrading contaminants. However, it relies on UV excitation and experiences rapid carrier recombination. To address these drawbacks, novel xylan‐based carbon dots@hydrogenated TiO2 (CDs@TiO2‐x) composited by direct Z‐scheme heterojunction is fabricated as a visible light‐driven photocatalytic material, which broadens the range of light absorption to visible light and suppresses the recombination of photogenerated carriers. The spindle‐shaped CDs@TiO2‐x has C/N/O/S groups, positive charges, and oxygen vacancies on its surface, and can degrade 89% of methylene blue and 87% of methyl orange within 90 min, and 99% of rhodamine B within 60 min in visible light. It also eradicates 99.9% of E. coli in 2 h and 97.1% of S. aureus in 2.5 h. These performances surpass CDs and TiO2‐x, and exhibit advantages in similar composite materials. The degradation pathways of dyes and the specific antibacterial processes induced by ROS are thoroughly investigated through LC‐MS testing and related enzyme activity assays. DFT calculations study the role of oxygen vacancies, heterojunction mechanism, and catalytic sites. This study has developed a novel nanocomposite with applications in both dye degradation and sterilization, offering insights for multifunctional materials based on photocatalysis and heterojunction. [ABSTRACT FROM AUTHOR]

Aromatic organoarsenic compounds (AOCs) have proven to be both a boon and a curse by boosting profit maximization in livestock production and at the same time contributing to the pollution of water bodies, the chief cornerstone of the ecosystem. Interestingly, photocatalytic degradation using nanomaterials has emerged as an effective method to mitigate AOC pollution. Thus, this study aims to review and analyze original research works directed toward the photocatalytic degradation of AOC in the aqueous environment. In this study, the photocatalytic degradation efficiency of various nanomaterials is investigated for different aromatic organoarsenic compounds. In addition, an empirical analysis was conducted on the impact of electron trapping and radical scavengers. Furthermore, photocatalytic degradation kinetics and mechanisms were pragmatically discussed. Also, recyclability, stability, and real‐life applicability were empirically evaluated. According to this review, most nanomaterial materials had maximal photocatalytic degradation efficiencies of >75% for most AOCs within an average time of 6–330 min. The radical scavenging study revealed that ●OH and O2● mechanistically play a major role in AOC degradation than electrons and holes. Additionally, it was shown that expended photocatalysts can be eluted mostly with H2O/NaOH and recycled up to 3–6 rounds with a degradation efficiency of >80% in most cases while maintaining their original structural integrity. This indicates that the method has the potential to be both environmentally friendly and industrially scalable. Ultimately, research gaps were highlighted, which can help researchers identify future research hotspots and open doors for technique advancement. [ABSTRACT FROM AUTHOR]

Industrial discharge of hazardous organic and synthetic chemicals, such as antibacterials and dyes, poses severe risks to human health and the environment. This study was conducted to address the urgent need for efficient and stable zinc-oxide-based photocatalysts to degrade such pollutants. A novel approach to synthesizing silver-loaded zinc oxide (Ag@Z) catalysts was introduced by using a simple and efficient combination of hydrothermal and precipitation methods. Comprehensive characterization of Ag@Z photocatalysts was performed using XRD, XPS, Raman, UV–vis adsorption, FTIR, and SEM, revealing an enhancement of structural, optical, and morphological properties in comparison to pure zinc oxide. Notably, the 5%Ag@Z catalyst exhibited the highest degradation efficiency among the other synthesized catalysts under UV-C light irradiation, and enhanced the degradation rate of pure zinc oxide (Z) by 1.14 and 1.64 times, for Triclosan (TCS) and Methylene Blue (MB), respectively. the effect of catalyst dose and initial concentration was studied. A mechanism of degradation was proposed after investigating the effect of major reactive species. The 5%Ag@Z catalyst increased the photostability, which is a major problem of zinc oxide due to photocorrosion after reusability. We found that 50% and 74% of energy consumption for the photocatalytic degradation of TCS and MB by 5%Ag@Z, respectively, was saved in compassion with zinc oxide. The remarkable photocatalytic performance and the good recovery rate of Ag@Z photocatalysts demonstrate their high potential for photocatalytic degradation of organic contaminants in water. [ABSTRACT FROM AUTHOR]

The great demand for visible‐light‐induced catalysts with high photocatalytic performance has stimulated extensive interest in constructing g‐C3N4‐based Z‐Scheme heterojunctions. In this research work, the g‐C3N4/Bi2O3 Z‐Scheme heterojunction by precipitation‐hydrothermal method was constructed, and characterized by various techniques. The g‐C3N4/Bi2O3‐1 composite exhibited a transient photocurrent response approximately 7 and 5 times higher than that of bare g‐C3N4 and Bi2O3, respectively, and showed higher visible photocatalytic activity with 99.8 % degradation of methylene blue (MB) within 75 min. Meanwhile, the pH effect on the photocatalytic degradation of MB was investigated. Radicals trapping experiments showed that •OH free radical played a predominant role for the degradation of MB, EPR analysis confirmed the presence of superoxide radicals, which combined with the band structure of the composites, confirmed the Z‐Scheme of the heterojunction. A possible mechanism for photocatalytic degradation of MB dyes in g‐C3N4/Bi2O3‐1 composites was also proposed. This study provided a new avenue for the development of novel g‐C3N4‐based Z‐Scheme heterojunction materials with prospective applications in the fields of energy and environment. [ABSTRACT FROM AUTHOR]

ZnO/Ag nanocomposite was prepared via in situ method by using silver nitrate and ZnSO4 as the raw material. ZnO and ZnO/Ag were characterized by utilizing SEM, UV-vis, XRD, FTIR, and so on. The photocataytic degradation behaviors of ZnO and ZnO/Ag for trimethylamine (TEA) in air and solution were studied. The results indicated that ZnO/Ag had better photocatalytic degradation properties on trimethylamine under the condition of 0.06 g catalyst, 2 h photocatalytic time, and 15 A light intensity, and the degradation rates of TEA were up to 44 and 67% in air and solution, respectively. Furtherly, ZnO and ZnO/Ag also indicated perfect photocatalytic degradation properties toward to organic compounds in wastewater. Especially, the harmless treatment of triethylamine was achieved by using photocatalytic degradation method that provided a novel method for treating triethylamine. In all the above results leaded to a good application prospect of ZnO/Ag in the degradation of organic compounds in air and solution. [ABSTRACT FROM AUTHOR]

Heterogenous photocatalysis is one of the promising methods of degradation of organic pollutants in the environment. This study developed a suitable and efficient method for photocatalytic degradation of Lambda-cyhalothrin LCY pesticide using Ce–ZnO nanocomposites under natural solar irradiation. Ce–ZnO was synthesized using the coprecipitation method and was ascertained through structural characterization. The crystal structure and crystallite size, surface morphology, functional groups present, and the elemental composition of the synthesized nanocomposites were determined by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and energy dispersive X-ray spectroscopy (EDAX), respectively. The average crystallite size of the nanocomposites was found to be 31.42 nm. The photocatalytic degradation of LCY was conducted in batches to obtain and determine the optimal conditions for the degradation of the pesticide. It was found that at optimum conditions; 100 ppm LCY initial concentration, 20 mg dose of the photocatalyst, and 10–11 UV index, Ce–ZnO were found to degrade about 92% of the initial concentration of LCY after 3 h of exposure to solar irradiation. It was found that Ce–ZnO possesses high photocatalytic activity against LCY and the kinetic of the degradation was found to fit the pseudo-first-order kinetic model. [ABSTRACT FROM AUTHOR]

Polymeric carbon nitride (PCN) is a kind of polymeric semiconductor that is widely popular in photocatalysis-related energy and environmental fields. However, the photocatalytic activity is still limited due to its poor conductivity and low charge separation efficiency. In this work, benzene rings were introduced to adjust the electronic structure of PCN, and then a PCN-based all-solid Z-scheme heterojunction was fabricated by combing multiwall carbon nanotubes (CNTs) and ferric oxide through precipitation and the in situ deposit method. Upon optimizing the ratio between PCN, CNTs, and Fe2O3, (PCN:CNTs:Fe2O3 = 10:1:3 by weight), the composites expressed superior photocatalytic degradation activity towards methylene blue (MB) and crystal violet (CV) compared with pristine PCN and Fe2O3. The MB degradation percentage achieved 90% in 75 min, and the CV up to 99.6% within 50 min. The Z-scheme mechanism was verified by band alignment and metal selective deposition. The CNTs in the heterojunction played the role of an electron shuttling mediator and hence improved charge separation efficiency. This work provides ideas for the construction of polymer-inorganic all-solid Z-scheme photocatalysts for practical applications. [ABSTRACT FROM AUTHOR]

This research work involves the bio-mediated production of titanium dioxide (TiO2) nanoparticles (NPs) using a bio-precipitation approach and the whole plant extract of Marchantia polymorpha, popularly known as common liverwort. In this study TTIP (Titaniumisopropoxide) was used as precursor of titanium and the function of reduction and capping of NPs was done by whole plant extract. The extract stabilizes the form and size of TiO2 NPs along with their synthesis. The formation of TiO2 NPs was confirmed by using various characterization techniques that are Ultraviolet–Visible (UV–Visible) spectroscopy, Fourier-Transform Infrared (FT-IR), Field Emission Scanning Electron Microscopy (FESEM) and X-ray diffraction (XRD). The UV–Visible analysis and energy band value confirms the synthesis of anatase type of TiO2 NPs. The XRD analysis also validates the formation of crystalline anatase phase of TiO2 NPs with crystallite size of 23 nm. FESEM analysis confirmed spherical shape of TiO2 NPs with average diameter of 28.6 nm. These biomediated TiO2 NPs were being utilized for the photocatalytic methylene blue dye degradation at different parameters like varied concentrations of dye, different amounts of TiO2 NPs and different pH. The optimum results were found to be at 5 ppm initial dye concentration, 40 mg catalyst, and at pH-6. The results indicated that these bio-mediated TiO2 NPs are suitable for photocatalytic degradation of methylene blue dye. [ABSTRACT FROM AUTHOR]

Water pollution has become a major concern due to the rapid development of industrialization and rise in chemical use, which poses a great risk to humans and environment. Herein, a novel nanocomposite of metal-free boron nitride quantum dots (BNQDs) supported on graphitic carbon nitride (g-C3N4) photocatalyst (BNQDs@g-C3N4) was successfully synthesized using a facile and green approach. The prepared nanocomposite exhibited exceptional photocatalytic activity in the degradation of aqueous waste pollutants, including organic dyes and pharmaceuticals under visible light irradiation, its worth mentioning, the rate constant of tetracycline removal was 0.064 mol−.L.min−1. The experimental results indicated that the significantly boosted photocatalytic activity of the BNQDs@g-C3N4 composite proved the energy gap modulation by the construction of heterojunction between the BNQDs and g-C3N4 in s-scheme photocatalyst. Theoretical calculations were done to calculate the crystal, electronic structures, and properties of BNQDs@g-C3N4. Theoretical results showed that loading of BNQDs on g-C3N4 provides an extended band edges that are more applicable in visible light-based photocatalysis process. Additionally, it offers additional bands that facilitate the passage of electrons between the valance and conduction bands. Finally, a possible s-scheme mechanism of the charge separation improvement was proposed by analyzing the experimental results and theoretical calculations. [ABSTRACT FROM AUTHOR]

Removal of organic dyes like methylene blue (MB) from industrial effluents serves as potential source of potable water. Photocatalytic degradation using sustainable catalyst is deemed to be an affordable solution. In this work, Nd2O3/MgO nanocomposite with different compositions (1, 3, and 5wt% Nd2O3 with MgO) have been achieved using hydrothermal synthesis and characterized extensively. Interestingly, increasing Nd2O3 proportion (1–5%) enhances light absorption, and decreases band gap and electron–hole recombination. The efficacy of the photocatalysts is tested with the degradation of MB dye, through optimizing Nd2O3/MgO proportion, contact time, catalyst dose, and pH. Interestingly, control experiments reveal that 5wt% Nd2O3/MgO achieve 99.6% degradation of MB in 90 min at pH 7, compared to 88.8% with bare MgO under same condition. Kinetic data show that 5wt% Nd2O3/MgO exhibits ca. 3 times higher degradation rate compared to MgO. For the first time, our work enable MgO-based sustainable photocatalyst development with minimum (5 wt%) rare-earth combination to achieve excellent photocatalytic degradation performance. [ABSTRACT FROM AUTHOR]

In the field of photocatalysis, heterojunction photocatalysts have garnered a lot of attention due to their high‐efficiency interfacial charge‐transfer property and their nanoarchitecture. Herein, GdFeO3/WS2 is successfully synthesized by the in‐situ growth method and holds significant catalytic properties and efficient degradation for tetracycline. Using WS2 as a co‐catalyst could reduce e‐ and h+ recombination, improving GdFeO3's photocatalytic performance. The GdFeO3/WS2 possesses a bandgap of 1.9 eV, 178.9 m2 g−1 specific surface area, 0.2 nm pore size, and a lifespan of 6 ns. The optimal GdFeO3/WS2 photocatalyst exhibits a maximum removal of 96.2 % at a tetracycline concentration of 10 mg/L, a pH of 3, and 40 mg of photocatalyst in an irradiation time of 90 min. Tetracycline has a higher photocatalytic efficiency in visible light (96.2 %) than in sunlight (72.6 %). Trapping tests revealed that the major reactive species for tetracycline removal in an aqueous solution are ⋅⋅OH, and ⋅⋅O2‐. The recycle experiment shows no deactivation of the GdFeO3/WS2 photocatalyst after 5 recycles. This study sheds light on the rational design of the GdFeO3/WS2 photocatalyst as a potential material for treating wastewater. [ABSTRACT FROM AUTHOR]

In the present work, ZnO/g-C3N4/biochar was prepared, and it was used for visible-light driven photocatalytic degradation of some colorants (methylene blue, rhodamine B, methyl orange) and some antibiotics (doxycycline, ciprofloxacin, amoxicilline). Biochar was prepared by pyrolysing Phragmites australis biomass. The ZnO/g-C3N4/biochar composite was synthesized with the alkaline hydrolysis method. The obtained materials were characterized by X-ray diffraction, scanning electron microscopy, transition electron microscopy, energy dispersive X-ray/elemental mapping, ultraviolet-visible-diffuse reflectance spectroscopy, photoluminescence spectroscopy, nitrogen adsorption/desorption isotherms and X-ray photoelectron spectroscopy. The results show that ZnO nanoparticles with a large surface area are highly dispersed on the g-C3N4 particle surface and biochar. The composite exhibits superior photocatalytic degradation ability toward doxycycline, a broad-spectrum antibiotic of the tetracycline compared with individual components (ZnO or g-C3N4) and satisfies stability after six treatment cycles. The kinetics and degradation mechanisms of doxycyline were also addressed. In addition, the present catalyst also exhibits the photocatalytic degradation of methylene blue, rhodamine B, methyl orange, ciprofloxacin and amoxicillin in visible-light regions. [ABSTRACT FROM AUTHOR]

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[Display omitted] • ZIF-67 derivative and GO co-modified enhanced the visible light catalytic performance of Bi 12 O 17 Cl 2. • Bi 12 O 17 Cl 2 /GO/Co 3 O 4 exhibits good activity, salt resistance, universality and water adaptability to antibiotics degradation. • A pH drift method measures the surface charge of Bi 12 O 17 Cl 2 /GO/Co 3 O 4. • The Z-scheme heterojunction photocatalytic mechanism for Bi 12 O 17 Cl 2 /GO/Co 3 O 4 is analyzed. • Three possible degradation pathways of levofloxacin by Bi 12 O 17 Cl 2 /GO/Co 3 O 4 are proposed. Levofloxacin (LVX) is difficult to be naturally degraded by microorganisms in water, and its residues in water will pose significant risks to human health and ecological environment. In this study, Bi 12 O 17 Cl 2 was used as the main body, Bi 12 O 17 Cl 2 /GO/Co 3 O 4 composite photocatalyst was prepared by pyrolysis of zeolitic imidazolate framework-67 (ZIF-67) combined with in-situ precipitation method and used to degrade LVX. A sequence of characterizations shows that addition of Co 3 O 4 and graphene oxide (GO) increases the visible light response range, improves the separation efficiency of photogenerated electrons and holes (e--h+) of photocatalyst, and thus improves the degradation efficiency of LVX. Under the optimal reaction conditions, the LVX degradation rate of Bi 12 O 17 Cl 2 /1.5GO/7.5Co 3 O 4 can reach 91.2 % at 120 min, and its reaction rate constant is the largest (0.0151 min−1), which is 2.17, 13.14 and 1.53 times that of Bi 12 O 17 Cl 2 , Co 3 O 4 and Bi 12 O 17 Cl 2 /7.5Co 3 O 4 , respectively, showing better photocatalytic performance. Simultaneously, the recycling stability of Bi 12 O 17 Cl 2 /1.5GO/7.5Co 3 O 4 was also verified. The capture experiments and electron EPR test results showed that superoxide radicals (•O 2 –) and photogenerated holes (h+) were the primary active substances in the reaction process. Finally, combined with HPLC-MS results, the photocatalytic degradation pathway of LVX was derived. This work will provide a theoretical basis for the design of Metal Organic Frameworks (MOFs)-derivative modified Bi 12 O 17 Cl 2 -based photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] Photocatalysts are one of the effective methods to degrade antibiotic contamination, but the efficiency is low and the toxicity is not well recognized. Deep lattice doping to induce defect generation is an effective way to improve the performance of photocatalysts. Here, defect-rich bromine-doped BiOCl-XBr photocatalysts were constructed with the help of small molecules inserted into the interlayer. The photocatalytic degradation performance of BiOCl-XBr was significantly enhanced, and its degradation rate was up to about 12 times that of BiOCl monomer. The main reasons for the stronger photocatalytic performance of BiOCl-XBr include Br doping to enhance visible light absorption, surface defects, and Bi valence changes to improve charge transport. The degradation of tetracycline (TC) produced more toxic intermediates, and the biotoxicity experiments also confirmed that the toxicity showed a trend of increasing and then decreasing, indicating that the more toxic intermediates were also mineralized during the degradation process. However, the mortality and hatching rate of zebrafish in the exposed group after degradation recovered but changed their activity pattern under light and dark conditions. This further warns us to focus on the toxicity changes after antibiotic degradation. Finally, based on the free radical analysis, the mechanism of photocatalytic degradation and detoxification of TC by BiOCl-XBr was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] The highly dispersed small-size metal co-catalysts can effectively improve the photocatalytic efficiency of semiconductor photocatalysts by separating photogenerated electrons and enriching active sites. However, this system tends to aggregate in the absence of carrier, resulting in the decrease of active sites. Here, MOF-derived carbon skeleton (MDCS) encapsulated Ni nanoparticles (Ni@MDCS) and BiOBr was loaded onto carbonized cellulose fibers (CCF) with the help of polydopamine (PDA) to construct high-performance and recyclable photocatalytic paper for photocatalytic degradation of organic dyes in water. The characterization results showed that MDCS promoted good dispersion of Ni nanoparticles and provided sufficient active sites. And Ni@MDCS as a co-catalyst accelerated the separation of photogenerated carriers in BiOBr. The PDA improved the loading state of Ni@MDCS on CCF and converted into N -doped C in the carbonization process for further increasing the transfer efficiency of photogenerated electrons. In the composite paper, the stable loading of Ni@MDCS/BiOBr hybrid on CCF improved the dispersion and reusability of photocatalyst. The degradation rate of rhodamine B on CCF/PDA-C/Ni@MDCS/BiOBr paper was as high as 94.6 % after 60 min visible light irradiation, which was about 2.5 times higher than that of CCF/BiOBr paper. During 10 cycles, CCF/PDA-C/Ni@MDCS/BiOBr paper maintained high photocatalytic efficiency and good structural stability. This study provides a new way for developing high-performance and recyclable photocatalytic paper. [ABSTRACT FROM AUTHOR]

Enhancing the efficiency of charge carrier separation is crucial for improving the performance of photocatalysts, thereby offering more effective solutions to energy and environmental pollution challenges. In this study, a carbon‐deficient ultra‐thin porous g‐C3N4 (Vc‐UPCN) was synthesized and subsequently was integrated with Bi2Fe4O9 (BFO) using a sonochemical self‐assembly technique, a Bi2Fe4O9/Vc‐UPCN (BC) photocatalyst featuring a Z‐scheme heterojunction. The BC catalyst was subjected to corona poling treatment to obtain BCp, which possesses an intrinsic electric field. Compared with pure BFO and Vc‐UPCN, the BC heterojunction exhibited higher photo‐generated electron–hole separation efficiency and photodegradation ability. Upon introduction of corona polarization, the photocatalytic performance of BC was further enhanced. Specifically, BCp‐15 (BFO/BC mass fraction = 15) achieved complete degradation of methylene blue (MB) within 30 min. BCp‐15 demonstrated that its degradation efficiency for MB was 1.28 times higher than that of BC‐15, 1.85 times higher than that of Vc‐UPCN, and impressive 7.69 times higher than that of pure BFO. The coupling effect of the heterojunction and ferroelectric polarization significantly improved the separation efficiency of photo‐generated carriers in BCp. This study is expected to provide a reference for the synergistic application of heterojunction and ferroelectric polarization in traditional semiconductor photocatalysis. [ABSTRACT FROM AUTHOR]

Surfactant‐assisted synthesis of photocatalysts for water treatment has received extensive attention from researchers. In this paper, a novel and efficient BiOBr/graphene oxide (BiOBr/GO) photocatalyst assisted by sodium dodecyl sulfate (SDS) was synthesized by a simple solvothermal method. Compared with use of other surfactants, like polyvinylpyrrolidone (PVP) and cetyltrimethylammonium bromide (CTAB), BiOBr/GO (SDS) shows outstanding photocatalytic degradation activity under optimal conditions: The degradation rate constants of BiOBr/GO (SDS) for oxytetracycline (OTC), tetracycline hydrochloride (TCH), brilliant blue (BB), and Rhodamine B (RhB) are 0.073, 0.057, 0.166, and 0.626 min−1, which are 2.8, 1.8, 9, and 1.5 times larger than pure BiOBr, respectively. In addition, after five cycles, BiOBr/GO (SDS) exhibits superior cycling stability. The enhanced photocatalytic performance can benefit from the introduction of SDS and GO. With the assistance of SDS in the preparation process, BiOBr/GO (SDS) nanosheets have good adsorption performance and dispersion effect, which is favorable for raising their specific surface area. Meanwhile, the electron capture effect of GO improves the transfer and separation efficiency of photogenerated carriers. Moreover, the possible degradation pathway for TCH is identified through liquid chromatography–mass spectrometry (LC–MS). This research can become a valuable reference for synthesizing photocatalysts with visible light response to degrading organic pollutants such as antibiotics and dyes. [ABSTRACT FROM AUTHOR]

[Display omitted] Y 2 O 3 is a cost-effective and environmentally friendly wide-band gap photocatalyst with extensive application potential. However, its limited ability to be excited by visible light restricts its practical uses. In this study, we coupled the narrow bandgap semiconductor AgI with Y 2 O 3 to form a Z-scheme heterostructure, significantly promoting its photocatalytic degradation activity. Characterization and experimental results demonstrated the formation of Y-O-Ag bonds through coupling with AgI, leading to an increase in oxygen vacancies in Y 2 O 3 , which promotes the chemisorption of H 2 O and O 2. The Y-O-Ag bond introduction promotes electron transfer, improves hole utilization, and boosts energy transfer efficiency, thus promoting the efficient generation of ·OH and 1O 2. The photocatalytic degradation rates of RhB and o-nitrophenol by 7.5% AgI/Y 2 O 3 were 26.5 and 4 times higher than those of pure Y 2 O 3 , respectively. This study provides theoretical support for the Z-scheme heterojunction to improve photocatalytic activity and offers efficient solutions and practical design ideas for sewage purification. [ABSTRACT FROM AUTHOR]