A visible light-induced, Cu-doped BiVO_4 photocatalyst was synthesized by a microwave hydrothermal method. The photocatalytic efficiency was investigated in the degradation of model water pollutants like Methylene Blu...A visible light-induced, Cu-doped BiVO_4 photocatalyst was synthesized by a microwave hydrothermal method. The photocatalytic efficiency was investigated in the degradation of model water pollutants like Methylene Blue(dye) and ibuprofen(pharmaceuticals), as well as the inactivation of Escherichia coli(bacteria). The Cu-doped BiVO4 samples showed better efficiency than undoped BiVO_4, and the 1 wt.% Cu-doped BiVO_4 sample showed the best efficiency. The degradation of Methylene Blue reached 95%, while the degradation of ibuprofen reached 75%, and the inactivation of E. coli reached 85% in irradiation with visible light. The appearance of additional absorption band shoulders and widening of the optical absorption in the visible range makes the prepared powder an efficient visible light-driven photocatalyst. Moreover, the formation of an in-gap energy state just above the valance band as determined by density functional theory(DFT) first principle calculation, facilitates the wider optical absorption range of the doped system. Similarly, this in-gap energy state also acts as an electron trap, which is favorable for the efficient separation and photoexcited charge carriers' transfer process. The formation of oxygen vacancies due to doping also improved the separation of the charge carrier, which promoted the trapping of electrons and inhibited electron hole recombination, thus increasing the photocatalytic activity. No decrease in the efficiency of the 1 wt.% Cu-doped BiVO_4 photocatalyst in the degradation of ibuprofen over three consecutive cycles revealed the stability of the photocatalyst towards photocorrosion. These findings highlight the multifunctional applications of Cu-doped BiVO_4 in wastewater containing multiple pollutants.展开更多
A BiVO_4 photoanode with exposed(040) facets was prepared to enhance its photoelectrochemical performance.The exposure of the(040) crystal planes of the BiVO_4 film was induced by adding NaCl to the precursor solution...A BiVO_4 photoanode with exposed(040) facets was prepared to enhance its photoelectrochemical performance.The exposure of the(040) crystal planes of the BiVO_4 film was induced by adding NaCl to the precursor solution. The asprepared BiVO_4 photoanode exhibits higher solar-light absorption and charge-separation efficiency compared to those of an anode prepared without adding Na Cl. To our knowledge,the photocurrent density(1.26 m A cm^(-2) at 1.23 V vs. RHE) of as-prepared BiVO_4 photoanode is the highest according to the reports for bare BiVO_4 films under simulated AM1.5 G solar light, and the incident photon-to-current conversion efficiency is above 35% at 400 nm. The photoelectrochemical(PEC)water-splitting performance was also dramatically improvedwith a hydrogen evolution rate of 9.11 lmol cm^(-2) h^(-1), which is five times compared with the BiVO_4 photoanode prepared without NaCl(1.82 lmol cm^(-2) h^(-1)). Intensity-modulated photocurrent spectroscopy and transient photocurrent measurements show a higher charge-carrier-transfer rate for this photoanode. These results demonstrate a promising approach for the development of high-performance BiVO_4 photoanodes which can be used for efficient PEC water splitting and degradation of organic pollutants.展开更多
Porous hollow microspheres of bismuth vanadate(BiVO_4) were successfully synthesized with the assistances of ethylenediamine tetraacetic(EDTA) and sodium dodecylbenzene sulfonate(SDBS) via hydrothermal method.The as-p...Porous hollow microspheres of bismuth vanadate(BiVO_4) were successfully synthesized with the assistances of ethylenediamine tetraacetic(EDTA) and sodium dodecylbenzene sulfonate(SDBS) via hydrothermal method.The as-prepared BiVO_4 samples were characterized by X-ray diffraction(XRD),field-emission scanning electron microscopy(FE-SEM) and UV-vis diffuse reflectance spectra(DRS).It was found that the ratio of EDTA and SDBS had a significant impact on the crystalline structure,size and morphology of BiVO_4 photocatalyst.The crystal phase could be adjusted by changing the mass ratio of EDTA and SDBS.The photocatalytic activities of different BiVO_4 samples were investigated through the degradation of RhB in the presence of H_2O_2 under visible light irradiation.The results indicated that the photocatalytic performance of the BiVO_4 microstructures was greatly influenced by the porous structure,morphology and band gap.The BiVO_4 sample prepared with the EDTA and SDBS ratio of 2:1 and total amount of 1.5 g have shown superior photocatalytic performance for its unique morphology,good porous structure and low band gap energy.展开更多
Photo-assisted Zn-air batteries(PZABs)hold promise for advancing sustainable energy systems.Herein,to address challenges associated with the cathode charging oxygen evolution reaction(OER),a photo-assisted hybrid Zn-a...Photo-assisted Zn-air batteries(PZABs)hold promise for advancing sustainable energy systems.Herein,to address challenges associated with the cathode charging oxygen evolution reaction(OER),a photo-assisted hybrid Zn-air battery(PHZAB)was constructed by employing photoelectrocatalytic glycerol oxidation reaction(GOR),which is thermodynamically favorable as a replacement for OER during the charging process.Based on element doping and cocatalyst loading strategies,the CoFe-LDH/Mo:BiVO_(4)photoanode was fabricated.Systematic photoelectrochemical tests demonstrate its excellent performance,with a GOR current density of 4.78 mA·cm^(-2) at 1.23 V vs.RHE,2.6 times that of the BiVO_(4),and an applied bias photon-to-current efficiency(ABPE)of 2.21%,3.7 times that of the BiVO_(4).Further analysis proves that these modification strategies enhance bulk carrier density,accelerate surface catalytic reactions,and effectively suppress carrier recombination,thus enhancing the photoelectrochemical(PEC)performance.Benefiting from the excellent performance of the CoFe-LDH/Mo:BiVO_(4)photoanode and the novel hybrid device structure design,the PHZAB exhibits a maximum round-trip efficiency of 206%(at 0.5 mA·cm^(-2))and a 68.7% electricity saving ratio under 1 sun illumination.Even at 2 mA·cm^(-2),a 156% round-trip efficiency and 64.2% electricity saving ratio were maintained.During the photoassisted-charging process,the optimized CoFe-LDH/Mo:BiVO_(4)photoanode yields a high GOR performance of a total production rate of 225 mmol·m^(-2)·h^(-1) and formic acid(FA)production rate of 133 mmol·m^(-2)·h^(-1).This work presents a novel bifunctional system toward the rational design of functional devices and materials for simultaneously converting solar energy into chemical energy and enabling reversible solar power storage for on-demand release.展开更多
In this study, we report the facile fabrication of a carbon quantum dots(CQDs)/BiVO_4 composite with efficient photocatalytic activity. Due to the excellent upconversion photoluminescence, as well as the photo-induced...In this study, we report the facile fabrication of a carbon quantum dots(CQDs)/BiVO_4 composite with efficient photocatalytic activity. Due to the excellent upconversion photoluminescence, as well as the photo-induced electron transfer and reservoir properties of CQDs, the CQDs/BiVO_4 composite exhibited superior photocatalytic performance in the degradation of rhodamine B(RhB) under the irradiation of simulated solar light. This study provides a strategy for the development of high-performance catalysts based on CQDs.展开更多
基金supported by the Global Research Laboratory Program of the National Research Foundation of Korea (NRF)funded by the Ministry of Education,Science and Technology (MEST) of Korea (No.2010-00339)
文摘A visible light-induced, Cu-doped BiVO_4 photocatalyst was synthesized by a microwave hydrothermal method. The photocatalytic efficiency was investigated in the degradation of model water pollutants like Methylene Blue(dye) and ibuprofen(pharmaceuticals), as well as the inactivation of Escherichia coli(bacteria). The Cu-doped BiVO4 samples showed better efficiency than undoped BiVO_4, and the 1 wt.% Cu-doped BiVO_4 sample showed the best efficiency. The degradation of Methylene Blue reached 95%, while the degradation of ibuprofen reached 75%, and the inactivation of E. coli reached 85% in irradiation with visible light. The appearance of additional absorption band shoulders and widening of the optical absorption in the visible range makes the prepared powder an efficient visible light-driven photocatalyst. Moreover, the formation of an in-gap energy state just above the valance band as determined by density functional theory(DFT) first principle calculation, facilitates the wider optical absorption range of the doped system. Similarly, this in-gap energy state also acts as an electron trap, which is favorable for the efficient separation and photoexcited charge carriers' transfer process. The formation of oxygen vacancies due to doping also improved the separation of the charge carrier, which promoted the trapping of electrons and inhibited electron hole recombination, thus increasing the photocatalytic activity. No decrease in the efficiency of the 1 wt.% Cu-doped BiVO_4 photocatalyst in the degradation of ibuprofen over three consecutive cycles revealed the stability of the photocatalyst towards photocorrosion. These findings highlight the multifunctional applications of Cu-doped BiVO_4 in wastewater containing multiple pollutants.
基金financial support provided by the National Nature Science Foundation of China(No.21576162,No.51578332,and No.21507085)the Shanghai Yangfan Program(14YF1401500)
文摘A BiVO_4 photoanode with exposed(040) facets was prepared to enhance its photoelectrochemical performance.The exposure of the(040) crystal planes of the BiVO_4 film was induced by adding NaCl to the precursor solution. The asprepared BiVO_4 photoanode exhibits higher solar-light absorption and charge-separation efficiency compared to those of an anode prepared without adding Na Cl. To our knowledge,the photocurrent density(1.26 m A cm^(-2) at 1.23 V vs. RHE) of as-prepared BiVO_4 photoanode is the highest according to the reports for bare BiVO_4 films under simulated AM1.5 G solar light, and the incident photon-to-current conversion efficiency is above 35% at 400 nm. The photoelectrochemical(PEC)water-splitting performance was also dramatically improvedwith a hydrogen evolution rate of 9.11 lmol cm^(-2) h^(-1), which is five times compared with the BiVO_4 photoanode prepared without NaCl(1.82 lmol cm^(-2) h^(-1)). Intensity-modulated photocurrent spectroscopy and transient photocurrent measurements show a higher charge-carrier-transfer rate for this photoanode. These results demonstrate a promising approach for the development of high-performance BiVO_4 photoanodes which can be used for efficient PEC water splitting and degradation of organic pollutants.
基金National Natural Science Foundations of China(Nos.51178093,51208086)Central University Project,China(No.2232013D3-10)
文摘Porous hollow microspheres of bismuth vanadate(BiVO_4) were successfully synthesized with the assistances of ethylenediamine tetraacetic(EDTA) and sodium dodecylbenzene sulfonate(SDBS) via hydrothermal method.The as-prepared BiVO_4 samples were characterized by X-ray diffraction(XRD),field-emission scanning electron microscopy(FE-SEM) and UV-vis diffuse reflectance spectra(DRS).It was found that the ratio of EDTA and SDBS had a significant impact on the crystalline structure,size and morphology of BiVO_4 photocatalyst.The crystal phase could be adjusted by changing the mass ratio of EDTA and SDBS.The photocatalytic activities of different BiVO_4 samples were investigated through the degradation of RhB in the presence of H_2O_2 under visible light irradiation.The results indicated that the photocatalytic performance of the BiVO_4 microstructures was greatly influenced by the porous structure,morphology and band gap.The BiVO_4 sample prepared with the EDTA and SDBS ratio of 2:1 and total amount of 1.5 g have shown superior photocatalytic performance for its unique morphology,good porous structure and low band gap energy.
基金the National Key Research and Development Program of China(No.2014CB932101)the National Natural Science Foundation of China,111 Project(No.B07004)+1 种基金Program for Changjiang Scholars and Innovative Research Team in University(No.IRT1205)the Fundamental Research Funds for the Central Universities(No.buctrc201527).
文摘Photo-assisted Zn-air batteries(PZABs)hold promise for advancing sustainable energy systems.Herein,to address challenges associated with the cathode charging oxygen evolution reaction(OER),a photo-assisted hybrid Zn-air battery(PHZAB)was constructed by employing photoelectrocatalytic glycerol oxidation reaction(GOR),which is thermodynamically favorable as a replacement for OER during the charging process.Based on element doping and cocatalyst loading strategies,the CoFe-LDH/Mo:BiVO_(4)photoanode was fabricated.Systematic photoelectrochemical tests demonstrate its excellent performance,with a GOR current density of 4.78 mA·cm^(-2) at 1.23 V vs.RHE,2.6 times that of the BiVO_(4),and an applied bias photon-to-current efficiency(ABPE)of 2.21%,3.7 times that of the BiVO_(4).Further analysis proves that these modification strategies enhance bulk carrier density,accelerate surface catalytic reactions,and effectively suppress carrier recombination,thus enhancing the photoelectrochemical(PEC)performance.Benefiting from the excellent performance of the CoFe-LDH/Mo:BiVO_(4)photoanode and the novel hybrid device structure design,the PHZAB exhibits a maximum round-trip efficiency of 206%(at 0.5 mA·cm^(-2))and a 68.7% electricity saving ratio under 1 sun illumination.Even at 2 mA·cm^(-2),a 156% round-trip efficiency and 64.2% electricity saving ratio were maintained.During the photoassisted-charging process,the optimized CoFe-LDH/Mo:BiVO_(4)photoanode yields a high GOR performance of a total production rate of 225 mmol·m^(-2)·h^(-1) and formic acid(FA)production rate of 133 mmol·m^(-2)·h^(-1).This work presents a novel bifunctional system toward the rational design of functional devices and materials for simultaneously converting solar energy into chemical energy and enabling reversible solar power storage for on-demand release.
基金supported by the National Natural Science Foundation of China(Grant Nos.51402194,51572128)
文摘In this study, we report the facile fabrication of a carbon quantum dots(CQDs)/BiVO_4 composite with efficient photocatalytic activity. Due to the excellent upconversion photoluminescence, as well as the photo-induced electron transfer and reservoir properties of CQDs, the CQDs/BiVO_4 composite exhibited superior photocatalytic performance in the degradation of rhodamine B(RhB) under the irradiation of simulated solar light. This study provides a strategy for the development of high-performance catalysts based on CQDs.
文摘水热法在FTO导电玻璃表面制备了Co_(3)O_(4)掺杂不同摩尔比例石墨烯的Co_(3)O_(4)/G(Graphene)薄膜,筛选出掺杂石墨烯比例最合适的Co_(3)O_(4)/G薄膜样品作为基底,使用旋涂法将Bi VO_(4)旋涂在其表面,成功制备出了(Co_(3)O_(4)/G)@BiVO_(4)复合薄膜结构的光电探测器。利用电化学工作站(CHI760E型)和氙灯(CEL-S500型)模拟太阳光对样品进行光电性能测试,利用拉曼光谱来检测石墨烯的存在,使用场发射扫描电子显微镜和透射电子显微镜对样品的微观形貌结构进行分析,使用X射线衍射和X射线光电子能谱对样品进行物相以及化学键态的分析,并采用了UV-3600紫外-可见分光光度计对样品的光吸收性能进行了测试。结果显示:Co_(3)O_(4)与石墨烯掺杂比例为1∶2时,Co_(3)O_(4)/G薄膜光电流最优,是纯Co_(3)O_(4)薄膜光电流的10.8倍;相对于纯Co_(3)O_(4)薄膜,(Co_(3)O_(4)/G)薄膜的形貌从均匀、致密的草状生长为了类似石墨烯的网状结构;利用旋涂法制备的(Co_(3)O_(4)/G)@Bi VO_(4)复合薄膜具有更高的光电流和光吸收能力,其光电流为Co_(3)O_(4)/G薄膜的6.3倍,响应度为2.52 m A·W^(-1),探测率可达2.693×10^(12)Jones。
