Lignin, a negatively charged, three-dimensional natural biopolymer, serves as an ideal support for metal catalysts due to its abundant functional groups and tunable chemical properties, which enable strong metal coordination and effective immobilization. Herein, we demonstrate a lignin-mediated Co/O co-doped Ag2S, symbolized as L-AgCoOS, bimetal oxysulfide catalyst via a facile hydrolysis method for the efficient reduction of toxic phenolic compounds (4-nitrophenol, 4-NP), organic dyes (methyl orange (MO), methylene blue (MB), rhodamine B (RhB), and heavy metal ions Cr(VI)) under dark conditions. Lignin, used to immobilize catalysts, also contributes to increasing the number of active catalytic sites and enhancing catalytic activity. The co-doping of transition metal cations and anions was employed to effectively regulate the electron transfer property of the catalyst, with oxygen doping modifying the energy band structure and cobalt providing heterovalent Co3+/Co2+ states that facilitate rapid electron hopping between Co2+ and Co3+ (Co2+ ↔ Co3+) to transfer for catalytic reduction of pollutants. Furthermore, the hybridization of O 2p and S 3p orbitals improved the structural stability of the catalyst. L-AgCoOS with an appropriate level of cobalt doping exhibited significantly enhanced catalytic reduction efficiency. Specifically, 5 mg of L-AgCoOS-2 could completely reduce 100 ml of 20 ppm 4-NP within 8 min, with the reaction rate constant of 0.26 min-1. Additionally, it achieved a complete reduction of 100 ml of 50 ppm MB, MO, RhB, and Cr(VI) in 4, 3, 4, and 4 min, respectively, with the reaction rate constant of 0.49, 0.51, 0.57, and 0.54 min-1. L-AgCoOS-2 also demonstrated excellent performance in treating mixed pollutants, maintaining high activity across a wide pH range, and good reusability. These results highlight the significant potential of L-AgCoOS-2 for practical applications in wastewater treatment.

Herein, a novel sulfur-doped AgBi(MoO4)2 oxysulfide (AgBiMoOS) catalyst was prepared via a simple and environmentally friendly method. The S-doping regulates the energy band gap structure of AgBi(MoO4)2, making it suitable for photocatalytic hydrogen evolution (PHER) and extending the visible light absorption range. The Sdoping transforms the hydrophobic AgBi(MoO4)2 into the hydrophilic AgBiMoOS, which is rich in oxygen vacancy defects, serving as active sites for trapping water molecules and activating H-O-H bonds to promote proton generation. Additionally, S-doping regulates the electronic structure of AgBi(MoO4)2, forming heterovalent Mo6+/Mo4+ states that serve as rapid hopping sites between the Mo6+ and Mo4+ cations for photogenerated electrons to transfer during the PHER reaction, thereby further enhancing PHER efficiency. The hydrophilic AgBiMoOS-2 with a higher concentration of oxygen vacancy defects and an optimal heterovalent n(Mo6+)/n (Mo4+) states ratio exhibits excellent PHER activity of 947.4 mu mol/h and an apparent quantum efficiency (AQE) of 5.61 % at 420 nm. Furthermore, the AgBiMoOS-2 demonstrates remarkable PHER stability, with no significant decrease in the PHER rate after six cycles. This study provides a practical approach for applying silver-bismuthmolybdenum oxysulfide catalysts in PHER.

Traditional Ag3SbS3 exhibits low efficiency in the catalytic reduction of pollutants due to its surface hydrophobicity, which limits its practical application. Herein, we demonstrate a hydrophilic oxygen-doped Ag3SbS3 bimetal oxysulfide (AgSbOS or Ag3SbS3) catalyst with heterovalent valence states for the efficient reduction of toxic phenolic compounds (4-NP), organic dyes (MO, MB, RhB), and heavy metal ions (Cr6 +)The O-doping transforms the hydrophobic Ag3SbS3 into hydrophilic AgSbOS, increasing the adsorption sites and electrochemical active sites on the surface of AgSbOS. Hydrogen peroxide-driven oxidizing the Sb3+ into Sb5+, regulation of the AgSbOS with optimal heterovalent n(Sb5+)/n(Sb3+ + Sb5+) states facilitates the rapid hopping of electrons between Sb3+ <-> Sb5+ to transfer for the catalytic reduction of pollutants, accelerating the catalytic reduction activity. Oxygen doping also regulates the energy band structure to facilitate electron transfer and enhances the specific surface area, further improving the catalytic reduction activity. AgSbOS with an appropriate amount of oxygen doping significantly enhances the catalytic reduction efficiency, with 10 mg of AgSbOS3 reducing 100 mL of 20 ppm 4-NP and Cr6+ in 12 and 8 min, respectively. Furthermore, this catalyst achieves a complete reduction of 100 mL of 50 ppm MO, MB, and RhB in 4, 6, and 8 min, respectively. AgSbOS-3 is also effective in treating mixed pollutants, demonstrating high activity over a wide pH range and good reuse stability. AgSbOS exhibits significant potential for wastewater treatment applications.

A novel Fe/S-BiOCl sulfur-oxychloride catalyst with oxygen vacancy (Vo) defects and heterovalent states was synthesized via a facile and environmentally friendly method for the efficient catalytic reduction of organic dyes (methyl orange, methylene blue, rhodamine B, 4-nitrophenol) and heavy metal Cr6+ in the presence of NaBH4 under dark conditions. The Fe/S co-doping regulates the energy band structure of BiOCl-3, reduces charge transfer resistance, and increases the number of electrochemically active surface sites. Hydrogen peroxide treatment optimizes the heterovalent states in Fe/S-BiOCl-3 and creates Vo defects. The Vo defects act as active sites for creating H* and transferring it to the pollutants for hydrogenation. At the same time, the heterovalent states facilitate rapid electron hopping between Fe2+ <-> Fe3+ / Bi3+ <-> Bi5+, promote the catalytic reduction of pollutants, and enhance catalytic reduction activity. The Fe/S-BiOCl-3 with optimal Fe/S doping and hydrogen peroxide treatment exhibits excellent catalytic reduction efficiency, ultimately reducing 100 mL of 20 ppm 4-NP, MO, MB, and RhB in 6 min and Cr6+ in 8 min. The mixture of organic compounds and heavy metal ions was reduced within 10 min. The Fe/S-BiOCl-3 also demonstrates good stability, maintaining over 94.2 % of its catalytic activity after 6 cycles. Therefore, the Fe/S-BiOCl sulfur-oxychloride catalyst shows promising potential for wastewater treatment applications.

Herein, a Mo/S co-doped BiOCl bimetal sulfur-oxychloride (Mo/S-BiOCl) catalyst was synthesized via a facile and green method. The catalyst exhibited outstanding reduction performance toward organic dyes, toxic phenolic compounds, and heavy metal ions under dark conditions. The hydrazine-regulated Mo/S-BiOCl with heterovalent Mo4+/Mo6+ states triggered oxygen vacancy defects to balance the valence charge. Oxygen vacancy defects serve as both an electron capture center and a reactive active site, which enhances pollutant adsorption and the following reduction. The heterovalent molybdenum states facilitate the rapid hopping of electrons between Mo4+ and Mo6+ to transfer, thereby accelerating the catalytic reduction activity. The introduction of sulfur regulates the energy band structure and improves stability by hybridization of S 3p and O 2p orbitals. The hydrazine-driven Mo/S-BiOCl-3 with an optimal n(Mo4+)/n(Mo4+ + Mo6+) ratio and rich oxygen vacancy defects can complete reduction 100 mL of 20 ppm methylene blue (MB) in 6 min, 20 ppm 4-nitrophenol (4-NP) in 14 min, 50 ppm rhodamine B (RhB) in 10 min, 50 ppm methyl orange (MO) in 10 min, and 50 ppm Cr(VI) in 14 min. Additionally, the pollutant-mixed wastewater was fully reduced within 18 min, highlighting its efficient multi-pollutant treatment capability. Due to their unique properties and outstanding performance, Mo/S-BiOCl catalysts show strong potential for applications in advanced materials and environmental remediation.

A novel AgVOS oxysulfide catalyst for rapid catalytic reduction of toxic organic substances and Cr(VI) under dark is synthesized by a facile method. With the V/O co-doping, the doped Ag2S catalyst has the effectively regulated electron transfer performance, the hydrazine-driven V5+-to-V4+ reduction to disturb charge equilibrium, and the formed sulfur vacancy balanced by oxygen doping to maintain charge equilibrium. The formed sulfur vacancy acts as the active site for electrophilic nucleophilic reaction, while the orbital hybridization of O-2p and S-3p stabilizes the valence state of S2-. A suitable ratio of n(V4+/V5+) is regulated during the hydrazine-driven synthesis to facilitate the electron transfer and enhance the V5+-to-V4+ reduction reaction. V/O co-doped AgVOS-3 prepared by a suitable hydrazine content exhibits super catalytic reduction performance of organic 4-NP (4-nitrophenol), MB (methyl blue), MO (methyl orange), and RhB (Rhodamine B, 20 ppm, 100 mL) dyes, which are completely reduced within 8, 8, 10, and 8 min, respectively. In comparison, Cr6+ (50 ppm, 100 mL) is also completely reduced within 6 min by AgVOS-3, indicating its good catalytic reduction activity for organic and inorganic mixture pollutants. Furthermore, AgVOS-3 has good stability after cyclic tests to maintain a reduction efficiency of 96.5%. Therefore, the AgVOS catalyst shows a promising application for industrial wastewater treatment.

Herein, we established a Zn3(OH)2(V2O7)(H2O)2/V-Zn(O,S) Z-scheme heterojunction (labeled ZnVO/V-Zn(O,S) with a heterovalent V4+/V5+ states and oxygen vacancies in both phases via a one-step in-situ hydrolysis method. The NaBH4 regulated the ZnVO/V-Zn(O,S)-3 with rich Vo and suitable n(V4+)/n(V5+) ratio achieved an excellent photocatalytic nitrogen fixation activity of 301.7 mu mol/(g center dot h) and apparent quantum efficiency of 1.148% at 420 nm without any sacrificial agent, which is 11 times than that of V-Zn(O,S). The Vo acts as the active site to trap and activate N2 molecules and to trap and activate H2O to produce the H for N2 molecules photocatalytic reduction. The rich Vo defects can also reduce the competitive adsorption of H2O and N2 molecules on the surface active site of the catalyst. The heterovalent vanadium states act as the photogenerated electrons, quickly hopping between V4+ and V5+ to transfer for the photocatalytic N2 reduction reaction. Additionally, the Z-scheme heterojunction effectively minimizes photogenerated carrier recombination. These synergistic effects collectively boost the photocatalytic nitrogen fixation activity. This study provides a practical method for designing Z-scheme heterojunctions for efficient photocatalytic N2 fixation under mild conditions. (c) 2025, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

A Co/O co-doped ZnS-based bimetal oxysulfide (labeled as ZnCoOS) with heterovalent Co2+/Co3+ states and rich sulfur vacancies (Vs) defects was designed via a facile method for photocatalytic hydrogen evolution reaction (PHER). ZnCoOS possesses excellent electrical conductivity and electron trapping capacity, providing more reactive active sites. Introducing Co-/O- to regulate ZnCoOS with abundant Vs defects acts as active sites to trap H2O molecules and activate H-O-H bonds, producing protons for H2 production. Hydrogen peroxide regulated ZnCoOS, offering suitable heterovalent Co2+/Co3+ states and providing sites for photogenerated electrons to rapidly hop between Co2+ and Co3+ for charge transfer during PHER. The ZnCoOS-3 with optimal hydrogen peroxide regulation achieved an excellent PHER rate of 2180 mu mol h- 1 and AQE of 19.11% at 365 nm, approximately 8 times higher than monometallic ZnOS and 5.5 times higher than ZnCoOS prepared without H2O2. Furthermore, ZnCoOS had good photocatalytic stability and durability. A rational mechanism to enhance PHER activity was also explored, providing new insights into the design and application of ZnCoOS bimetal oxysulfide for PHER.

ObjectiveCoastal cities are susceptible to both internal and external factors, making them difficult to recover under the frequent influence of human activities. These factors collectively contribute to the vulnerability of marine ecosystems, posing numerous challenges for the protection and construction of coastal cities in terms of ecology, culture, and environment. Among these challenges, the imbalance of ecological and cultural resources stands out prominently. This research aims to explore the construction of an ecological and marine cultural composite landscape network, so as to promote the coupling and coordination between marine culture and the ecological environment, and optimize the allocation of ecological and marine cultural landscape resources. This will not only protect important ecological resources and cultural habitats but also strengthen the connections between them.MethodsIntegrated application of MSPA, landscape connectivity evaluation, MCR model, K-means clustering, Linkage Mapper, and cultural corridor spatial pattern model enable the construction of ecological network and marine-cultural network for the research area. The coupling of the aforesaid ecological network and cultural network forms a composite landscape network pattern. An evaluation indicator system for the coupling degree of ecological and cultural functions is constructed, and the entropy weight method is used to calculate index weights and the coupling coordination degree. Functional evaluations and hierarchical optimizations of the composite landscape network are conducted.ed on the evaluation results of the gravity model, these corridors are classified into first-class, second-class, and third-class corridors, forming the spatial pattern of the Quanzhou ecological network.ResultsThe MCR model identifies 136 potential ecological corridors, totaling 4381.139 km. Based on the evaluation results of the gravity model, these corridors are classified into first-class, second class, and third-class corridors, forming the spatial pattern of the Quanzhou ecological network. Linkage Mapper identifies 19 cultural corridors, totaling 888.001 km, and combined with the influence scope of core cultural landscape information points, the spatial pattern of the Quanzhou cultural network is constructed. The dissemination range of cultural landscape information points is between 0.04 km and 15.19 km. The integration of the ecological and cultural networks results in a composite pattern of Quanzhou’s marine cultural and ecological landscape network. Considering the corridor radiation range, a 1,000 m buffer along the composite corridor network is taken as the evaluation object for each corridor. Using the coupling coordination degree calculation formula, the coupling coordination degree of 62 corridors is calculated and classified according to the coupling coordination degree standard, forming the evaluation results of Quanzhou’s ecological and marine cultural composite landscape network. The results indicate that 1 corridor is severely imbalanced, 16 moderately imbalanced, 32 basically balanced, 11 moderately balanced, and 2 in excellent balance.ConclusionThe regional comprehensive coupling coordination degree of the composite corridors reveals a gradual decrease as the distance from coastal and central urban areas increases. The results show that the degree of coupling coordination presents the spatial characteristics of increasing from the coastal and central urban areas to the periphery. This phenomenon mainly considers the following two factors: first, the quality of the ecological environment in the northern, western and central regions is better, the ecological network coverage is complete, and the distribution of marine cultural resources is balanced; second, although the coastal and central urban areas have dense cultural heritage sites and prominent cultural values, the lack of ecological sources and urban environmental problems have led to a decrease in the coordination of their landscape corridors. Therefore, in the optimization of the complex landscape corridor, we should focus on the restoration of the ecological problems in the coastal areas and the central urban areas, and transform the cultural-oriented network into an ecological-cultural dual-function network Secondly, in the interior of the basic coordination section corridor, should focus on the ecological function and regional characteristics to enhance the cultural value. The construction and optimization strategy of Quanzhou’s ecological and marine culture composite landscape network provides a basis for the integration, flow, efficient utilization and overall protection of Quanzhou’s ecological and cultural resources, it also provides a reference template for the comprehensive coordinated protection of ecology and culture and the integrated sustainable development of coastal cities.

Herein, we demonstrate a Mo/S co-doped BiOBr-based bimetal bismuth sulfur-oxybromide (Mo/S-BiOBr) catalyst with heterovalent molybdenum states and abundant oxygen vacancy defects for photocatalytic hydrogen evolution (PHER) via a facile method. Mo/S co-doping adjusts the energy band structure of BiOBr and expands its visible light absorption. Hydrazine regulates the molybdenum with heterovalent states while endowing Mo/S-BiOBr with oxygen vacancy defects to balance the valence-charge deviations from electrical neutrality induced by Mo6+ -> Mo4+. These oxygen-vacancy defects act as active sites for capturing water molecules and activating the H-O-H bond to produce protons for hydrogen generation. The heterovalent Mo6+/Mo4+ states act as photogenerated electron hosts to hop fast between Mo6+ and Mo4+, facilitating efficient electron transfer for the PHER. The hybridization between S 3p and O 2p orbitals improves the stability of continuous PHER. The hydrazine-regulated Mo/S-BiOBr-3 with an optimal n(Mo4+)/n(Mo4+ + Mo6+) ratio and abundant oxygen vacancy defects exhibit an excellent PHER activity of 710.5 mu mol h-1 at a catalyst weight of 50 mg and an apparent quantum efficiency (AQE) of 13.9% at 420 nm. After six recycles, the H2 yield of Mo/S-BiOBr-3 decreased by only about 3.5%, indicating its good stability and durability. This work provides a practical approach to using bismuth-based oxyhalides in the PHER. A novel Mo/S co-doped BiOBr-based bimetal bismuth sulfur-oxybromide catalyst with heterovalent molybdenum states and abundant oxygen vacancy defects exhibits an excellent photocatalytic hydrogen evolution activity of 710.5 mu mol h-1.

V/S co-doped SnO2 bimetal sulfur-oxides catalysts labeled as (Sn,V)(1-x)(S,O)(2-y) or (SnVSO) with heterovalent state and oxygen vacancy defect are prepared via a green and facile method. The presence of SnVSO in the heterovalent states of Sn4+/Sn2+ and V5+/V4+ facilitates the rapid transfer of the electrons. It improves the electronic charge lifetime, accelerating the efficiency of the catalytic reduction of pollutants. The V/S co-doped SnO2 regulates the bandgap energy structure. The hydrazine adjusts the heterovalent metal states to reduce Sn4+ to Sn2+ and V5+ to V4+. Also, it introduces oxygen vacancies to SnVSO to maintain the charge equilibrium and increase the active surface reactive sites, which enhance the catalytic activity. The SnVSO-3 prepared with 0.4 mL hydrazine exhibits excellent catalytic activity, which wholly reduces 20 ppm of 100 mL methyl orange (MO), rhodamine B (RhB), methylene blue (MB), hexavalent chromium (Cr6+), and 4-nitrophenol (4-NP) within 6 min. In addition, the SnVSO-3 also has good stability after repeated 6 runs with a reduction efficiency of 96.8%. Therefore, the V/S co-doped SnO2 sulfur oxide catalysts have a promising potential for reducing Cr6+ and organic pollutants.

Herein, an Ag/S co-doped Bi2O3-based sulfur oxide catalyst was prepared via a facile green method.

The rising accumulation of pollutants, including heavy metals and toxic organics, necessitates effective environmental remediation to protect health and biological systems. In this study, a cubic cerianite CeO2-like Co/S co -doped CeO2 sulfur -oxide catalyst (labeled as CeCoOS) with super catalytic reduction performance of pollutants with NaBH4 as a reducing agent under dark was prepared via a green and facile preparation method. Transition metal Co2+-cation and S2 - -anion co -doped CeO2 adjusted the energy bandgap and introduced oxygen vacancy (Vo), which converted Ce4+ around Vo into Ce3+ to maintain electric neutrality. The heterovalent Ce4+/ Ce3+ states in Co/S-CeO2 enhance the electron lifetime and facilitate fast electron transfer. The valence transition between Ce4+/Ce3+ and Vo make the Co/S co -doped in CeO2 catalyst increase its electrochemically active surface sites and accelerate the pollutants reduction reaction. The CeCoOS-3 with Co/S dopants has an excellent catalytic reduction activity to completely reduce 20 ppm toxic 4 -NP in 10 min, 50 ppm organic dyes of MB, RhB, and MO in 6 min, and 50 ppm heavy metal Cr6+ in 10 min. The CeCoOS-3 sulfur -oxide catalyst also exhibited excellent stability in the reusability test. Therefore, CeCoOS sulfur -oxide catalysts are expected to be used for dye decolorization, detoxification of organic toxins, and reduction of electroplating wastewater.

A novel Ce/S co-doped TiO2 sulfur-oxide catalyst (labeled TiCeOS) with heterovalent metal states and oxygen-vacancy defects was synthesized for effective photocatalytic nitrogen fixation into ammonia under visible light.

Organic pollutants in industrial and agricultural wastewater can be dangerous to both human health and the environment. Therefore, it is important to develop methods for continuous catalytic reduction of these pollutants under dark conditions as sunlight has geographical and temporal limitations due to different regions, weather conditions, and Earth's rotation. This could have significant implications for practical wastewater treatment. In this study, we successfully synthesized bimetallic vanadium bismuth oxy-sulfo bromide (labeled as VBiOSBr) catalysts using a simple precipitation method by doping V/S into BiOBr to from (Bi,V)(S,O)Br. The morphology, structure, optical absorption properties, electron-hole recombination rate, and reduction performance of the catalysts were examined in detail. The catalyst displayed a tetragonal phase with an energy band gap and specific surface area of approximately 1.93 eV and 22.1 m2/g, respectively. The 1-VBiOSBr catalyst prepared with n(V): n(Bi): n(KBr): n(C2H5NS) = 1: 1: 1: 1 had the best catalytic activity. Within just 14 min, this catalyst removed 98.7% and 96.96% of 4-NP and Cr6+, respectively. The VBiOSBr catalyst remained stable and efficient even after the seventh run, still achieving a removal rate of 94.7%. The study proposed a possible mechanism for 4-NP and Cr6+ reduction activity. The catalyst's simple manufacturing process and its ability to reduce pollutants under dark conditions make it a promising system for practical application in the continuous removal of organic pollutants. So, the VBiOSBr bimetallic catalyst has great potential as a candidate for wastewater treatment technologies.

A novel La/O co-doped SnS oxysulfide catalyst (labeled SnLaOS) with heterovalent tin states and sulfur vacancy defects is successfully synthesized for effective catalytic reduction of toxic organics heavy metal ions with NaBH4 in the dark. La/O co-doped and hydrogen peroxide-driven SnLaOS catalyst with suitable heterovalent Sn2+/Sn4+ states and sulfur vacancy defects exhibited excellent catalytic reduction capability. The 100 mL 20 ppm of 4-nitrophenol (4-NP) and 50 ppm of rhodamine-B (RhB), methylene blue (MB), methyl orange (MO), and Cr(VI) solution are entirely reduced by 5 mg SnLaOS-3 within 10, 12, 12, 16, and 14 min, respectively, with durable stability. Synergistic transition metal La3+-cation and O2--anion co-doped SnS adjusted the energy bandgap and introduced sulfur vacancy defects, and the hydrogen peroxide-driven regulated the SnLaOS with suitable Sn4+/Sn2+ states ratio. The sulfur vacancies in SnLaOS provide active sites for adsorbed proton for pollutants reduction, and heterovalent Sn2+/Sn4+ states in SnLaOS facilitates electrons efficient transfer through electron hopping between Sn2+ and Sn4+ for pollutants reduction. This study provides a novel efficient catalyst for the water pollutants treatment. La/O co-doped and hydrogen peroxide-driven SnLaOS with proportional heterovalent Sn2+/Sn4+ states and sulfur vacancy defects for effective catalytic reduction of toxic organics and heavy metal ions pollutants. image

Bismuth oxyhalide (BiOI) has been used for photoelectrochemical catalysis in the field of catalytic hydrogen evolution, but it in a single-phase form has hardly been reported for photocatalytic hydrogen evolution reaction (PHER). Herein, we designed a W/S co-doped BiOI-based superhydrophilic catalyst with oxygen vacancy-rich defects and heterovalent valence states for efficient PHER under visible light. The W/S doping in BiOI not only adjusts the energy band structure and expands the visible light response range, but also transforms its hydrophobicity into superhydrophilicity, with which the gas bubble amount can be reduced and PHER activity enhanced. The introduction of sulfur regulates the content of oxygen vacancies which enhance the active surface sites for capturing water molecules and activating the H-O-H bond. The added tungsten exists in different valence states of W 6+ and W 5+ which is beneficial for electron hopping and PHER activity. The W/S-BiOI-3 with the suitable W/S doping content exhibits the highest visible-light PHER rate of 9.46 mmol center dot g-- 1 center dot h- 1 , with an apparent quantum efficiency (AQE) of 9.7 % at 420 nm. W/S-BiOI-3 shows excellent PHER activity, stability, and durability, which provides a feasible scheme for other bismuth-based halogen oxides to be used in PHER.

Nitrogen fixation reaction via photocatalysis offers a green and promising strategy for renewable NH3 synthesis, and catalysts with high-efficiency photocatalytic properties are essential to the process. Herein, we demonstrate a W-doped Sb2OS2 bimetal oxysulfide catalyst (labeled as SbWOS) with abundant oxygen vacancies, heterovalent metal states, and hydrophilic surfaces for nitrogen photoreduction to ammonia. The SbWOS-3 with suitable W-doping exhibited excellent nitrogen fixation activity of 408.08 mu molg(-1)h(-1) and an apparent quantum efficiency (AQE) of 1.88% at 420 nm and a solar-to-ammonia (STA) conversion efficiency of 0.082% in pure water under AM1.5G light irradiation. The W-doping not only transforms hydrophobic Sb2OS2 into a hydrophilic catalyst, making it easier for H2O molecules adsorbed on the SbWOS surface and catalyzed into protons, but also endows the SbWOS catalyst with rich oxygen vacancies, acting as the active sites for trapping and activating the N-2 molecule, and for trapping and activating H2O to produce the protons for the N-2 photocatalytic reduction reaction. The hydrazine drives the SbWOS catalyst with the heterovalent metal states, which acts as the photogenerate electrons quickly hopping between W5+ and W6+ to transfer for the N-2 reduction reaction. This study provides a feasible scheme for applying oxygen vacancy defects, heterovalent metal states, and surface hydrophobic-to-hydrophilic wetting engineering in bimetal oxysulfide for N-2 photoreduction to ammonia.

Herein, we demonstrate a Co/S co-doped TiO2 bimetal sulfur oxide catalyst with heterovalent Co states and abundant oxygen vacancy defects for the photocatalytic nitrogen reduction reaction in an ambient environment.

Researchers are presently focused on finding catalysts to efficiently reduce organic dyes used in industries like textiles, cosmetics, and food, aiming to reduce environmental pollution. This study aims to synthesize highly efficient, stable, and non-toxic bimetallic catalysts to lessen the environmental impact of organic dyes such as methylene blue (MB), methylene orange (MO), and rhodamine B (RhB). A composite catalyst (denoted as Ce-BiOBr/Bi2S3), was synthesized using a co-precipitation method for the catalytic reductions of RhB, MB, and MO organic dyes under dark. The co-incorporation of Ce/S into BiOBr notably enhanced the catalytic reduction efficiency of the resulting Ce-BiOBr/Bi2S3 catalyst. Activated by NaBH4 as a source of H, the catalyst exhibited significant catalytic activity in reducing dyes under dark conditions. The findings indicate that Ce-BiOBr/Bi2S3 activated with NaBH4 can complete MO, MB, and RhB dyes within 10, 12, and 18 min. The porous structure of Ce-BiOBr/Bi2S3 boosts the reductions as it can intercept MO, MB, and RhB species. Moreover, the hopping of electrons between Ce-BiOBr and Bi2S3 components allows for providing the needed electrons for reduction. The synergistic combination of Ce-BiOBr and Bi2S3 components significantly improves the reduction of pollutants. The stability and reusability of Ce-BiOBr/Bi2S3 were evaluated and showed an excellent retaining efficiency of 95.2 % through six consecutive tests for the NaBH4-activated reduction. The porous structure, consisting of micro-rods and particle spheres in Ce-BiOBr/Bi2S3, contributed to its robust structure and reusability, establishing it as an excellent catalyst for environmental remediation. In conclusion, we strongly endorse the Ce-BiOBr/Bi2S3 catalyst, synthesized through environmentally friendly processes, for its high efficiency and promising potential for industrial applications.