In this study,a graphitic carbon nitride(g-C_(3)N_(4))based ternary catalyst Cu O/Cu Fe_(2)O_(4)/gC_(3)N_(4)(CCCN)is successfully prepared thorough calcination method.After confirming the structure and composition of ...In this study,a graphitic carbon nitride(g-C_(3)N_(4))based ternary catalyst Cu O/Cu Fe_(2)O_(4)/gC_(3)N_(4)(CCCN)is successfully prepared thorough calcination method.After confirming the structure and composition of CCCN,the as-synthesized composites are utilized to activate persulfate(PS)for the degradation of organic contaminant.While using tetracycline hydrochloride(TC)as pollutant surrogate,the effects of initial p H,PS and catalyst concentration on the degradation rate are systematically studied.Under the optimized reaction condition,CCCN/PS is able to give 99%degradation extent and 74%chemical oxygen demand removal in assistance of simulated solar light,both of which are apparently greater than that of either Cu O/Cu Fe_(2)O_(4)and pristine g-C_(3)N_(4).The great improvement in degradation can be assignable to the effective separation of photoinduced carriers thanks to the integration between Cu O/Cu Fe_(2)O_(4)and g-C_(3)N_(4),as well as the increased reaction sites given by the g-C_(3)N_(4)substrate.Moreover,the scavenging trials imply that the major oxidative matters involved in the decomposition are hydroxyl radicals(·OH),superoxide radicals(·O_(2)^(-))and photo-induced holes(h^(+)).展开更多
Photoelectrochemical(PEC)water splitting capable of reducing and oxidizing water into hydrogen and oxygen in a generation mode of spatial separation has gained extensive popularity.In order to effectively produce hydr...Photoelectrochemical(PEC)water splitting capable of reducing and oxidizing water into hydrogen and oxygen in a generation mode of spatial separation has gained extensive popularity.In order to effectively produce hydrogen at the photocathode of a PEC cell,the photoanode,where the oxygen evolution reaction occurs,should be systematically developed on priority.In particular,WO3 has been identified as one of the most promising photoanode materials owing to its narrow band gap and high valence band position.Its practical implementation,however,is still limited by excessive electron–hole recombination and poor water oxidation kinetics.This review presents the various strategies that have been studied for enhancing the PEC water oxidation performance of WO3,such as controlling the morphology,introducing defects,constructing a heterojunction,loading a cocatalyst,and exploiting the plasmonic effect.In addition,the possible future research directions are presented.展开更多
A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV...A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV-Vis diffuse reflectance, scanning electron microscopy, and X-ray photoelectron spectroscopic characterizations. Photocatalytic experiments demonstrated that the synthesized BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst exhibited excellent photocatalytic performance toward the degradation of tetracycline hydrochloride(TCH) under simulated sunlight. Furthermore, the TCH degradation rate of BiOCl0.9I0.1/15%β-Bi2O3 increased by 27.6% and 61.4% compared with those of the pure BiOCl0.9I0.1 and pure β-Bi2O3, respectively. Due to the multiple vacancies and valence states possessed by BiOCl0.9I0.1/x%β-Bi2O3, namely Bi5+, Bi(3-x)+, Bi5+–O, Bi3+–O, I- and I3-, the charge separation in photocatalysis reactions can be effectively promoted. The Mott-Schottky measurements indicate that the conduction band(CB) level of BiOCl0.9I0.1/15%β-Bi2O3 becomes more negative relative to that of BiOCl0.9I0.1, guaranteeing an advantageous effect on the redox ability of the photocatalyst. This study provides a new bright spot for the construction of high-performance photocatalysts.展开更多
In this work,a covalent organic framework(COF),which is constructed by the building blocks of[5,10,15,20-tetrakis(4-aminophenyl)porphinato]copper(Ⅱ)(CuTAPP)and p-benzaldehyde,is employed to integrate with TiO_(2) for...In this work,a covalent organic framework(COF),which is constructed by the building blocks of[5,10,15,20-tetrakis(4-aminophenyl)porphinato]copper(Ⅱ)(CuTAPP)and p-benzaldehyde,is employed to integrate with TiO_(2) for the purpose of establishing a Z-scheme hybrid.Within the system,isonicotinic acid performs the role of a bridge that connects the two components through a coordination bond.Further photocatalytic application reveals the hybrid framework is able to catalyze CO_(2) conversion under simulated solar light,resulting in CO production rate of 50.5 μmol g^(-1)·h^(-1),about 9.9 and 24.5 times that of COF and pristine TiO_(2),respectively.The ameliorated catalytic performance owes much to the por-phyrin block acting as photosensitizer that augments the light absorbance,and the establishment of Z-scheme system between the inorganic and orga nic comp on ents that enhances the separati on of the carriers.In addition,the chemical bridge also ensures a steady usage and stable charge delivery in the catalysis.Our study sheds light on the development of versatile approaches to covalently in corporate COFs with inorga nic semic on ductors.展开更多
A bismuth vanadate(BiVO4)photoanode with a cocatalyst consisting of NiFe layered double‐hydroxide(NiFe‐LDH)nanoparticles was fabricated for photoelectrochemical(PEC)water splitting.NiFe‐LDH nanoparticles,which can ...A bismuth vanadate(BiVO4)photoanode with a cocatalyst consisting of NiFe layered double‐hydroxide(NiFe‐LDH)nanoparticles was fabricated for photoelectrochemical(PEC)water splitting.NiFe‐LDH nanoparticles,which can improve light‐absorption capacities and facilitate efficient hole transfer to the surface,were deposited on the surface of the BiVO4 photoanode by a hydrothermal method.All the samples were characterized using X‐ray diffraction,scanning electron microscopy,and diffuse‐reflectance spectroscopy.Linear sweep voltammetry and current‐time plots were used to investigate the PEC activity.The photocurrent response of NiFe‐LDH/BiVO4 at 1.23 V vs the reversible hydrogen electrode was higher than those of Ni(OH)2/BiVO4,Fe(OH)2/BiVO4 and pure BiVO4 electrodes under visible‐light illumination.NiFe‐LDH/BiVO4 also gave a superior PEC hydrogen evolution performance.Furthermore,the stability of the NiFe‐LDH/BiVO4 photoanode was excellent compared with that of the bare BiVO4 photoanode,and offers a novel method for solar‐assisted water splitting.展开更多
The construction of rich phase interfaces to increase active reaction area in hybrid materials is an excellent strategy to improve electrochemical performance.Under this guideline,MIL-101@OX-metal organic framework(MO...The construction of rich phase interfaces to increase active reaction area in hybrid materials is an excellent strategy to improve electrochemical performance.Under this guideline,MIL-101@OX-metal organic framework(MOF)is constructed by the"MOF on MOF"method,then converts to MIL-101@NiFe-layered double hydroxides(LDH)by in situ transformation in alkaline solution.MIL-101@NiFe-LDH shows excellent electrochemical water oxidation performance.It needs only an overpotential of 215 m V to drive10 m A/cm^(2)of oxygen evolution reaction(OER),which is less than that of NiFe-LDH,MIL-101.In addition,MIL-101@NiFe-LDH has the smallest Tafel slope(55.1 mV/dec)compared with Ni Fe-LDH(61.1 m V/dec),MIL-101(150.8 m V/dec).The excellent water oxidation activity is due to the high phase interfaces derived from high specific surface area of MOF.This work offers an alternative method for making MOF/LDH heterostructures with an optimized phase interfaces and provides new insights for OER.展开更多
Photocatalytic CO_(2)reduction is a promising solution to simultaneously provide renewable chemical fuels and address the greenhouse effect.However,designing practical photocatalysts with advanced architectures remain...Photocatalytic CO_(2)reduction is a promising solution to simultaneously provide renewable chemical fuels and address the greenhouse effect.However,designing practical photocatalysts with advanced architectures remains challenging.Herein,we report the preparation of a novel CdIn_(2)S_(4)/TiO_(2)binary heterojunction via an in situ solvothermal approach,which exhibits superior photocatalytic activity for sunlight-driven CO_(2)reduction.The CdIn_(2)S_(4)/TiO_(2)composites exhibit significantly enhanced photocatalytic performance for CO_(2)reduction compared to unmodified TiO_(2).Among them,the 3%CdIn_(2)S_(4)/TiO_(2)composite has optimal CO and CH_(4)evolution rates of 18.32 and 1.03μmol·g^(–1)·h^(–1),respectively.The yield of CO is 4.7 times higher than that of pristine TiO_(2).This improved photocatalytic activity of the CdIn_(2)S_(4)/TiO_(2)heterostructure can be attributed to its large surface area,extended light absorption range and high separation efficiency of photogenerated electron-hole pairs,which are supported by the results of photoluminescence spectroscopy and the photoelectrochemical measurements.Moreover,the photocatalytic mechanism based on the binary CdIn_(2)S_(4)/TiO_(2)heterojunction is proposed and separation process of photogenerated electron-hole pairs is discussed.In brief,we aim to provide insights into the application of TiO_(2)in energy conversion processes through the construction of heterogeneous junctions.展开更多
The cobalt-carbonate(CoCi)/NiFeOOH double-layer co-catalyst was prepared on bismuth vanadate(BiVO_(4)).Compared with the same type of electrode(Co-Pi/NiFeOOH/BiVO_(4)and Co-Sil/NiFeOOH/BiVO_(4)),the photoelectrochemic...The cobalt-carbonate(CoCi)/NiFeOOH double-layer co-catalyst was prepared on bismuth vanadate(BiVO_(4)).Compared with the same type of electrode(Co-Pi/NiFeOOH/BiVO_(4)and Co-Sil/NiFeOOH/BiVO_(4)),the photoelectrochemical(PEC)performance of the composite electrode presents the most excellent performance.The Co-Ci/NiFeOOH/BiVO_(4)electrode prepared by photoelectric deposition(PED)achieves a photocurrent density of 4.1 mA/cm^(2)at 1.23 V vs RHE,and the applied bias photon-current efficiency(ABPE)is up to 0.95%.In addition,with the help of the equivalent circuit fitting in electrochemical impedance spectroscopy(EIS),the charge transfer resistance(R_(ct))of Co-Ci/NiFeOOH/BiVO_(4)is only 108.9Ω,which is 16%that of BiVO_(4).The enhanced PEC performance of Co-Ci/NiFeOOH/BiVO_(4)in the double-layer cocatalyst system is attributed to the outstanding advantages of Co-Ci cocatalyst in oxygen vacancy defects,superior to other cobalt-based catalysts in promoting charge transfer and improving the kinetics of water oxidation.This makes Co-Ci co-catalyst become one of the favorable competitors in the field of photoelectric catalysis.展开更多
As one of the highly effective methods to prepare catalysts for photocatalytic reduction of CO2 into valueadded chemicals,using metalloporphyrin as light-harvesting mixed ligand to modify metal-organic framework(MOF)i...As one of the highly effective methods to prepare catalysts for photocatalytic reduction of CO2 into valueadded chemicals,using metalloporphyrin as light-harvesting mixed ligand to modify metal-organic framework(MOF)is very valuable since it can greatly improve the prophyrin dispersibility and consequently inhibit its potential agglomeration.Herein,we employed a one-pot synthetic strategy to chemically immobilize Cu(II)tetra(4-carboxylphenyl)porphyrin(CuTCPP)into UiO-66 MOF structure through coordination mode.Meanwhile,in-situ growth of TiO2 nanoparticles onto the MOF is actualized with the generation of CuTCPP c UiO-66/TiO2(CTU/TiO2)composites.Under Xe lamp irradiation(λ>300 nm),the catalytic result presents that an optimal value of 31.32 μmol g^-1 h^-1 CO evolution amount,about 7 times higher than that of pure TiO2 was obtained through the photocatalysis.It is supposed owning to a consistent augment of light absorption derived from chemically implanted porphyrin derivative,which is simultaneously functioning with an efficacious separation of photo-induced carries given by the newly engendered composites between MOF and TiO2,an effective catalytic activity and approving recyclability of CTU/TiO2 can be achieved in the photocatalytic reduction of CO2 into CO.展开更多
Photoelectrochemical(PEC)water splitting is an effective strategy to convert solar energy into clean and renewable hydrogen energy.In order to carry out effective PEC conversion,researchers have conducted a lot of exp...Photoelectrochemical(PEC)water splitting is an effective strategy to convert solar energy into clean and renewable hydrogen energy.In order to carry out effective PEC conversion,researchers have conducted a lot of exploration and developed a variety of semiconductors suitable for PEC water splitting.Among them,metal oxides stand out due to their higher stability.Compared with traditional oxide semiconductors,ferrite-based photoelectrodes have the advantages of low cost,small band gap,and good stability.Interestingly,due to the unique characteristics of ferrite,most of them have various tunable features,which will be more conducive to the development of efficient PEC electrode.However,this complex metal oxide is also troubled by severe charge recombination and low carrier transport efficiency,resulting in lower conversion efficiency compared to theoretical value.Based on this,this article reviews the structure,preparation methods,characteristics and modification strategies of various common ferrites.In addition,we analyzed the future research direction of ferrite for PEC water splitting,and looked forward to the development of more efficient catalysts.展开更多
The serious surface charge recombination and fatigued photogenerated carriers transfer of the BiVO_(4)photoanode restrict its photoelectrochemical(PEC)water splitting performance.In this work,nickel fluoride(NiF_(2))i...The serious surface charge recombination and fatigued photogenerated carriers transfer of the BiVO_(4)photoanode restrict its photoelectrochemical(PEC)water splitting performance.In this work,nickel fluoride(NiF_(2))is applied to revamp pure BiVO_(4)photoanode by using a facile electrodeposition method.As a result,the asprepared NiF_(2)/BiVO_(4)photoanode increases the dramatic photocurrent density by approximately 180%compared with the pristine BiVO_(4)photoanode.Furthermore,the correlative photon-to-current conversion efficiency,the charge injection,and the separation efficiency,as well as the hydrogen generation of the composite photoanode have been memorably enhanced due to the synergy of NiF_(2)and BiVO_(4).This study may furnish a dependable guidance in fabricating the fluoride-based compound/semiconductor composite photoanode system.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.21663027 and 21808189)the Key Science and Technology Foundation of Gansu Province(No.20YF3GA021)+2 种基金the Innovation funding program of Universities of Gansu province(No.2020B-091)the Opening Project of Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education(No.LYJ18205)the Promotion Project of Young-Teacher Research-capacity of Northwest Normal University(No.NWNU-LKQN-18-5)。
文摘In this study,a graphitic carbon nitride(g-C_(3)N_(4))based ternary catalyst Cu O/Cu Fe_(2)O_(4)/gC_(3)N_(4)(CCCN)is successfully prepared thorough calcination method.After confirming the structure and composition of CCCN,the as-synthesized composites are utilized to activate persulfate(PS)for the degradation of organic contaminant.While using tetracycline hydrochloride(TC)as pollutant surrogate,the effects of initial p H,PS and catalyst concentration on the degradation rate are systematically studied.Under the optimized reaction condition,CCCN/PS is able to give 99%degradation extent and 74%chemical oxygen demand removal in assistance of simulated solar light,both of which are apparently greater than that of either Cu O/Cu Fe_(2)O_(4)and pristine g-C_(3)N_(4).The great improvement in degradation can be assignable to the effective separation of photoinduced carriers thanks to the integration between Cu O/Cu Fe_(2)O_(4)and g-C_(3)N_(4),as well as the increased reaction sites given by the g-C_(3)N_(4)substrate.Moreover,the scavenging trials imply that the major oxidative matters involved in the decomposition are hydroxyl radicals(·OH),superoxide radicals(·O_(2)^(-))and photo-induced holes(h^(+)).
基金financially supported by the National Natural Science Foundation of China (21808189, 21663027)the Science and Technology Support Project of Gansu Province (1504GKCA027)+2 种基金the Program for Innovative Research Team (NWNULKQN-15-2)the Opening Project of Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control (GKLECPC-12)the Opening Project of Key Laboratory of Green Catalysis of Sichuan Institutes of High Education (LYJ18205)~~
文摘Photoelectrochemical(PEC)water splitting capable of reducing and oxidizing water into hydrogen and oxygen in a generation mode of spatial separation has gained extensive popularity.In order to effectively produce hydrogen at the photocathode of a PEC cell,the photoanode,where the oxygen evolution reaction occurs,should be systematically developed on priority.In particular,WO3 has been identified as one of the most promising photoanode materials owing to its narrow band gap and high valence band position.Its practical implementation,however,is still limited by excessive electron–hole recombination and poor water oxidation kinetics.This review presents the various strategies that have been studied for enhancing the PEC water oxidation performance of WO3,such as controlling the morphology,introducing defects,constructing a heterojunction,loading a cocatalyst,and exploiting the plasmonic effect.In addition,the possible future research directions are presented.
文摘A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV-Vis diffuse reflectance, scanning electron microscopy, and X-ray photoelectron spectroscopic characterizations. Photocatalytic experiments demonstrated that the synthesized BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst exhibited excellent photocatalytic performance toward the degradation of tetracycline hydrochloride(TCH) under simulated sunlight. Furthermore, the TCH degradation rate of BiOCl0.9I0.1/15%β-Bi2O3 increased by 27.6% and 61.4% compared with those of the pure BiOCl0.9I0.1 and pure β-Bi2O3, respectively. Due to the multiple vacancies and valence states possessed by BiOCl0.9I0.1/x%β-Bi2O3, namely Bi5+, Bi(3-x)+, Bi5+–O, Bi3+–O, I- and I3-, the charge separation in photocatalysis reactions can be effectively promoted. The Mott-Schottky measurements indicate that the conduction band(CB) level of BiOCl0.9I0.1/15%β-Bi2O3 becomes more negative relative to that of BiOCl0.9I0.1, guaranteeing an advantageous effect on the redox ability of the photocatalyst. This study provides a new bright spot for the construction of high-performance photocatalysts.
基金financially supported by the National Natural Science Foundation of China (21663027 and 21808189)the Key Science and Technology Foundation of Gansu Province (20YF3GA021)+2 种基金the Innovation funding program of Universities of Gansu province (2020B-091)the Opening Project of Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education (LYJ18205)the Promotion Project of Young-Teacher Researchcapacity of Northwest Normal University (NWNU-LKQN-18-5).
文摘In this work,a covalent organic framework(COF),which is constructed by the building blocks of[5,10,15,20-tetrakis(4-aminophenyl)porphinato]copper(Ⅱ)(CuTAPP)and p-benzaldehyde,is employed to integrate with TiO_(2) for the purpose of establishing a Z-scheme hybrid.Within the system,isonicotinic acid performs the role of a bridge that connects the two components through a coordination bond.Further photocatalytic application reveals the hybrid framework is able to catalyze CO_(2) conversion under simulated solar light,resulting in CO production rate of 50.5 μmol g^(-1)·h^(-1),about 9.9 and 24.5 times that of COF and pristine TiO_(2),respectively.The ameliorated catalytic performance owes much to the por-phyrin block acting as photosensitizer that augments the light absorbance,and the establishment of Z-scheme system between the inorganic and orga nic comp on ents that enhances the separati on of the carriers.In addition,the chemical bridge also ensures a steady usage and stable charge delivery in the catalysis.Our study sheds light on the development of versatile approaches to covalently in corporate COFs with inorga nic semic on ductors.
基金supported by the National Natural Science Foundation of China(21663027,51262028,21261021)the Science and Technology Support Project of Gansu Province(1504GKCA027)+2 种基金the Program for the Young Innovative Talents of Longyuanthe Program for Innovative Research Team(NWNULKQN-15-2)the Undergraduate Academic Innovative Research Team of Northwest Normal University~~
文摘A bismuth vanadate(BiVO4)photoanode with a cocatalyst consisting of NiFe layered double‐hydroxide(NiFe‐LDH)nanoparticles was fabricated for photoelectrochemical(PEC)water splitting.NiFe‐LDH nanoparticles,which can improve light‐absorption capacities and facilitate efficient hole transfer to the surface,were deposited on the surface of the BiVO4 photoanode by a hydrothermal method.All the samples were characterized using X‐ray diffraction,scanning electron microscopy,and diffuse‐reflectance spectroscopy.Linear sweep voltammetry and current‐time plots were used to investigate the PEC activity.The photocurrent response of NiFe‐LDH/BiVO4 at 1.23 V vs the reversible hydrogen electrode was higher than those of Ni(OH)2/BiVO4,Fe(OH)2/BiVO4 and pure BiVO4 electrodes under visible‐light illumination.NiFe‐LDH/BiVO4 also gave a superior PEC hydrogen evolution performance.Furthermore,the stability of the NiFe‐LDH/BiVO4 photoanode was excellent compared with that of the bare BiVO4 photoanode,and offers a novel method for solar‐assisted water splitting.
基金financially supported by the National Natural Science Foundation of China(No.21808189)the National Natural Science Foundation of Gansu(No.20JR5RA523)the Young Teachers’Research Ability Improvement Project of Northwest Normal University(NWNU-LKQN2020-01)。
文摘The construction of rich phase interfaces to increase active reaction area in hybrid materials is an excellent strategy to improve electrochemical performance.Under this guideline,MIL-101@OX-metal organic framework(MOF)is constructed by the"MOF on MOF"method,then converts to MIL-101@NiFe-layered double hydroxides(LDH)by in situ transformation in alkaline solution.MIL-101@NiFe-LDH shows excellent electrochemical water oxidation performance.It needs only an overpotential of 215 m V to drive10 m A/cm^(2)of oxygen evolution reaction(OER),which is less than that of NiFe-LDH,MIL-101.In addition,MIL-101@NiFe-LDH has the smallest Tafel slope(55.1 mV/dec)compared with Ni Fe-LDH(61.1 m V/dec),MIL-101(150.8 m V/dec).The excellent water oxidation activity is due to the high phase interfaces derived from high specific surface area of MOF.This work offers an alternative method for making MOF/LDH heterostructures with an optimized phase interfaces and provides new insights for OER.
基金supported by the National Natural Science Foundation of China(Grant No.21663027)the Key Research and Development Program of Gansu Province(Grant No.21YF5GA068)+1 种基金the Innovative Research Team for Science and Technology of Shaanxi Province(Grant No.2022TD-04)Industry Supporting Project for Gansu Institution of Higher Learning(Grant No.2021CYZC-26).
文摘Photocatalytic CO_(2)reduction is a promising solution to simultaneously provide renewable chemical fuels and address the greenhouse effect.However,designing practical photocatalysts with advanced architectures remains challenging.Herein,we report the preparation of a novel CdIn_(2)S_(4)/TiO_(2)binary heterojunction via an in situ solvothermal approach,which exhibits superior photocatalytic activity for sunlight-driven CO_(2)reduction.The CdIn_(2)S_(4)/TiO_(2)composites exhibit significantly enhanced photocatalytic performance for CO_(2)reduction compared to unmodified TiO_(2).Among them,the 3%CdIn_(2)S_(4)/TiO_(2)composite has optimal CO and CH_(4)evolution rates of 18.32 and 1.03μmol·g^(–1)·h^(–1),respectively.The yield of CO is 4.7 times higher than that of pristine TiO_(2).This improved photocatalytic activity of the CdIn_(2)S_(4)/TiO_(2)heterostructure can be attributed to its large surface area,extended light absorption range and high separation efficiency of photogenerated electron-hole pairs,which are supported by the results of photoluminescence spectroscopy and the photoelectrochemical measurements.Moreover,the photocatalytic mechanism based on the binary CdIn_(2)S_(4)/TiO_(2)heterojunction is proposed and separation process of photogenerated electron-hole pairs is discussed.In brief,we aim to provide insights into the application of TiO_(2)in energy conversion processes through the construction of heterogeneous junctions.
基金financially supported by the National Natural Science Foundation of China(Nos.52173277 and 21808189)the Key Science and Technology Foundation of Gansu Province,China(No.20YF3GA021)the Natural Science Foundation of Gansu Province,China(No.20JR5RA523).
文摘The cobalt-carbonate(CoCi)/NiFeOOH double-layer co-catalyst was prepared on bismuth vanadate(BiVO_(4)).Compared with the same type of electrode(Co-Pi/NiFeOOH/BiVO_(4)and Co-Sil/NiFeOOH/BiVO_(4)),the photoelectrochemical(PEC)performance of the composite electrode presents the most excellent performance.The Co-Ci/NiFeOOH/BiVO_(4)electrode prepared by photoelectric deposition(PED)achieves a photocurrent density of 4.1 mA/cm^(2)at 1.23 V vs RHE,and the applied bias photon-current efficiency(ABPE)is up to 0.95%.In addition,with the help of the equivalent circuit fitting in electrochemical impedance spectroscopy(EIS),the charge transfer resistance(R_(ct))of Co-Ci/NiFeOOH/BiVO_(4)is only 108.9Ω,which is 16%that of BiVO_(4).The enhanced PEC performance of Co-Ci/NiFeOOH/BiVO_(4)in the double-layer cocatalyst system is attributed to the outstanding advantages of Co-Ci cocatalyst in oxygen vacancy defects,superior to other cobalt-based catalysts in promoting charge transfer and improving the kinetics of water oxidation.This makes Co-Ci co-catalyst become one of the favorable competitors in the field of photoelectric catalysis.
基金financially supported by the National Natural Science Foundation of China (21663027, 21808189)the Science and Technology Support Project of Gansu Province (1504GKCA027)
文摘As one of the highly effective methods to prepare catalysts for photocatalytic reduction of CO2 into valueadded chemicals,using metalloporphyrin as light-harvesting mixed ligand to modify metal-organic framework(MOF)is very valuable since it can greatly improve the prophyrin dispersibility and consequently inhibit its potential agglomeration.Herein,we employed a one-pot synthetic strategy to chemically immobilize Cu(II)tetra(4-carboxylphenyl)porphyrin(CuTCPP)into UiO-66 MOF structure through coordination mode.Meanwhile,in-situ growth of TiO2 nanoparticles onto the MOF is actualized with the generation of CuTCPP c UiO-66/TiO2(CTU/TiO2)composites.Under Xe lamp irradiation(λ>300 nm),the catalytic result presents that an optimal value of 31.32 μmol g^-1 h^-1 CO evolution amount,about 7 times higher than that of pure TiO2 was obtained through the photocatalysis.It is supposed owning to a consistent augment of light absorption derived from chemically implanted porphyrin derivative,which is simultaneously functioning with an efficacious separation of photo-induced carries given by the newly engendered composites between MOF and TiO2,an effective catalytic activity and approving recyclability of CTU/TiO2 can be achieved in the photocatalytic reduction of CO2 into CO.
基金This work was financially supported by the National Natural Science Foundation of China(21808189,52173277)National Natural Science Foundation of Gansu province(No.20JR5RA523)the Young Teachers’Research Ability Improvement Project of Northwest Normal University(NWNULKQN2020-01).
文摘Photoelectrochemical(PEC)water splitting is an effective strategy to convert solar energy into clean and renewable hydrogen energy.In order to carry out effective PEC conversion,researchers have conducted a lot of exploration and developed a variety of semiconductors suitable for PEC water splitting.Among them,metal oxides stand out due to their higher stability.Compared with traditional oxide semiconductors,ferrite-based photoelectrodes have the advantages of low cost,small band gap,and good stability.Interestingly,due to the unique characteristics of ferrite,most of them have various tunable features,which will be more conducive to the development of efficient PEC electrode.However,this complex metal oxide is also troubled by severe charge recombination and low carrier transport efficiency,resulting in lower conversion efficiency compared to theoretical value.Based on this,this article reviews the structure,preparation methods,characteristics and modification strategies of various common ferrites.In addition,we analyzed the future research direction of ferrite for PEC water splitting,and looked forward to the development of more efficient catalysts.
基金This work was financially supported by the National Key Research and Development Program of China(Grant No.2017YFC0602306)the National Natural Science Foundation of China(Grant No.21808189)National Natural Science Foundation of Gansu Province(Grant No.20JR5RA523).
文摘The serious surface charge recombination and fatigued photogenerated carriers transfer of the BiVO_(4)photoanode restrict its photoelectrochemical(PEC)water splitting performance.In this work,nickel fluoride(NiF_(2))is applied to revamp pure BiVO_(4)photoanode by using a facile electrodeposition method.As a result,the asprepared NiF_(2)/BiVO_(4)photoanode increases the dramatic photocurrent density by approximately 180%compared with the pristine BiVO_(4)photoanode.Furthermore,the correlative photon-to-current conversion efficiency,the charge injection,and the separation efficiency,as well as the hydrogen generation of the composite photoanode have been memorably enhanced due to the synergy of NiF_(2)and BiVO_(4).This study may furnish a dependable guidance in fabricating the fluoride-based compound/semiconductor composite photoanode system.
