Photocatalytic water splitting has emerged as a new frontier for converting solar energy to green H_(2) and value-added chemicals.Nevertheless,great challenges still remain for developing efficient photocatalysts for ...Photocatalytic water splitting has emerged as a new frontier for converting solar energy to green H_(2) and value-added chemicals.Nevertheless,great challenges still remain for developing efficient photocatalysts for pure water splitting without sacrificial agents.In this work,we demonstrate that doping hexagonal ZnIn_(2)S_(4)(ZIS) with Pd single atoms(Pd_(0.03)/ZIS) can serve as a highly efficient photocatalyst for pure water splitting to simultaneously produce H_(2) and H_(2)O_(2) without any sacrificial agents.Results from aberration-corrected high-angle annular dark field scanning transmission electron microscopy,X-ray fine spectroscopy,insitu electron paramagnetic resonance and diffuse Fourier transform infrared spectroscopy reveal that doping ZIS with Pd single atoms facilitates the formation of S vacancies(S_(v)),where the photogenerated electrons can transfer to Pd single atoms,as a result of enhanced separation of electron-hole pairs and improved photocatalytic performance.Impressively,Pd_(0.03)/ZIS displays a stoichiometric ratio of H_(2) and H_(2)O_(2) with the productivity of 1,037.9 and 1,021.4μmol g^(-1)h^(-1),respectively,which has largely outperformed pure ZIS and other reported catalysts for pure water splitting.This work provides an efficient photocatalyst for water splitting to produce H_(2) and H_(2)O_(2),which may attract rapid interest in materials science,chemistry,and heterogeneous catalysis.展开更多
TiO_(2)is a promising photocatalyst due to its high thermodynamic stability and non-toxicity.However,its applications have been still limited because of the high recombination rate of electron-hole pairs.Herein,we sho...TiO_(2)is a promising photocatalyst due to its high thermodynamic stability and non-toxicity.However,its applications have been still limited because of the high recombination rate of electron-hole pairs.Herein,we show that by combining heterojunction construction and electronic structure regulation,the electron-hole pairs in TiO_(2)can be effectively separated for enhanced photocatalytic hydrogen evolution.The optimized Cu_(7)S_(4)nanosheet decorated TiO_(2)achieves much enhanced H_(2)evolution rate(11.5 mmol·g−1·h−1),which is 13.8 and 4.2 times of that of TiO_(2)and Cu_(7)S_(4)/TiO_(2),respectively.The results of photoluminescence spectroscopy,transient photocurrent spectra,ultraviolet-visible diffuse reflectance spectra,and electrochemical impedance spectroscopy collectively demonstrate that the enhanced photocatalytic performance of Air-Cu_(7)S_(4)/TiO_(2)is attributed to the effective separation of charge carriers and widened photoresponse range.The electron paramagnetic resonance and X-ray photoelectron spectroscopy results indicate that the increase of Cu2+in the Cu_(7)S_(4)nanosheet after calcination can promote the charge transfer.This work provides an effective method to improve the electron migration rate and charge separation of TiO_(2),which holds great significance for being extended to other material systems and beyond.展开更多
As a versatile energy carrier,H_(2) is considered as one of the most promising sources of clean energy to tackle the current energy crisis and environmental concerns,which can be produced from photocatalytic water spl...As a versatile energy carrier,H_(2) is considered as one of the most promising sources of clean energy to tackle the current energy crisis and environmental concerns,which can be produced from photocatalytic water splitting.However,solar-driven photocatalytic H_(2) production from pure water in the absence of sacrificial reagents remains a great challenge.Herein,we demonstrate that the incorporation of Ru single atoms(SAs)into ZnIn_(2)S_(4)(Ru-ZIS)can enhance the light absorption,reduce the energy barriers for water dissociation,and construct a channel(Ru-S)for separating photogenerated electron−hole pairs,as a result of a significantly enhanced photocatalytic water splitting process.Impressively,the productivity of H_(2) reaches 735.2μmol g^(-1) h^(-1) under visible light irradiation in the absence of sacrificial agents.The apparent quantum efficiency(AQE)for H_(2) evolution reaches 7.5% at 420 nm,with a solarto-hydrogen(STH)efficiency of 0.58%,which is much higher than the value of natural synthetic plants(~0.10%).Moreover,Ru-ZIS exhibits steady productivity of H_(2) even after exposure to ambient conditions for 330 days.This work provides a unique strategy for constructing charge transfer channels to promote the separation of photogenerated electron−hole pairs,which may motivate the fundamental researches on catalyst design for photocatalysis and beyond.展开更多
基金financially supported by the National Key R&D Program of China(2020YFB1505802)the Ministry of Science and Technology of China(2017YFA0208200)+2 种基金the National Natural Science Foundation of China(22025108,U21A20327,22121001)Guangdong Provincial Natural Science Fund for Distinguished Young Scholars(2021B1515020081)the start-up support from Xiamen University。
文摘Photocatalytic water splitting has emerged as a new frontier for converting solar energy to green H_(2) and value-added chemicals.Nevertheless,great challenges still remain for developing efficient photocatalysts for pure water splitting without sacrificial agents.In this work,we demonstrate that doping hexagonal ZnIn_(2)S_(4)(ZIS) with Pd single atoms(Pd_(0.03)/ZIS) can serve as a highly efficient photocatalyst for pure water splitting to simultaneously produce H_(2) and H_(2)O_(2) without any sacrificial agents.Results from aberration-corrected high-angle annular dark field scanning transmission electron microscopy,X-ray fine spectroscopy,insitu electron paramagnetic resonance and diffuse Fourier transform infrared spectroscopy reveal that doping ZIS with Pd single atoms facilitates the formation of S vacancies(S_(v)),where the photogenerated electrons can transfer to Pd single atoms,as a result of enhanced separation of electron-hole pairs and improved photocatalytic performance.Impressively,Pd_(0.03)/ZIS displays a stoichiometric ratio of H_(2) and H_(2)O_(2) with the productivity of 1,037.9 and 1,021.4μmol g^(-1)h^(-1),respectively,which has largely outperformed pure ZIS and other reported catalysts for pure water splitting.This work provides an efficient photocatalyst for water splitting to produce H_(2) and H_(2)O_(2),which may attract rapid interest in materials science,chemistry,and heterogeneous catalysis.
基金supported by the National Key R&D Program of China(No.2020YFB1505802)the Ministry of Science and Technology(No.2017YFA0208200)+1 种基金the National Natural Science Foundation of China(Nos.22025108,U21A20327,and 22121001)the start-up fundings from Xiamen University.
文摘TiO_(2)is a promising photocatalyst due to its high thermodynamic stability and non-toxicity.However,its applications have been still limited because of the high recombination rate of electron-hole pairs.Herein,we show that by combining heterojunction construction and electronic structure regulation,the electron-hole pairs in TiO_(2)can be effectively separated for enhanced photocatalytic hydrogen evolution.The optimized Cu_(7)S_(4)nanosheet decorated TiO_(2)achieves much enhanced H_(2)evolution rate(11.5 mmol·g−1·h−1),which is 13.8 and 4.2 times of that of TiO_(2)and Cu_(7)S_(4)/TiO_(2),respectively.The results of photoluminescence spectroscopy,transient photocurrent spectra,ultraviolet-visible diffuse reflectance spectra,and electrochemical impedance spectroscopy collectively demonstrate that the enhanced photocatalytic performance of Air-Cu_(7)S_(4)/TiO_(2)is attributed to the effective separation of charge carriers and widened photoresponse range.The electron paramagnetic resonance and X-ray photoelectron spectroscopy results indicate that the increase of Cu2+in the Cu_(7)S_(4)nanosheet after calcination can promote the charge transfer.This work provides an effective method to improve the electron migration rate and charge separation of TiO_(2),which holds great significance for being extended to other material systems and beyond.
基金financially supported by the National Key R&D Program of China(2020YFB1505802)the Ministry of Science and Technology(2017YFA0208200)+1 种基金the National Natural Science Foundation of China(22025108,U21A20327,and 22121001)the start-up funding from Xiamen University.
文摘As a versatile energy carrier,H_(2) is considered as one of the most promising sources of clean energy to tackle the current energy crisis and environmental concerns,which can be produced from photocatalytic water splitting.However,solar-driven photocatalytic H_(2) production from pure water in the absence of sacrificial reagents remains a great challenge.Herein,we demonstrate that the incorporation of Ru single atoms(SAs)into ZnIn_(2)S_(4)(Ru-ZIS)can enhance the light absorption,reduce the energy barriers for water dissociation,and construct a channel(Ru-S)for separating photogenerated electron−hole pairs,as a result of a significantly enhanced photocatalytic water splitting process.Impressively,the productivity of H_(2) reaches 735.2μmol g^(-1) h^(-1) under visible light irradiation in the absence of sacrificial agents.The apparent quantum efficiency(AQE)for H_(2) evolution reaches 7.5% at 420 nm,with a solarto-hydrogen(STH)efficiency of 0.58%,which is much higher than the value of natural synthetic plants(~0.10%).Moreover,Ru-ZIS exhibits steady productivity of H_(2) even after exposure to ambient conditions for 330 days.This work provides a unique strategy for constructing charge transfer channels to promote the separation of photogenerated electron−hole pairs,which may motivate the fundamental researches on catalyst design for photocatalysis and beyond.