采用溶剂热法在不同反应体系和温度下,制备了一系列Cu In S2(CIS)粉体。CIS粉体的物相、形貌、光吸收性能分别用X射线衍射(XRD)仪、场发射扫描电镜(FESEM)、透射电镜(TEM)、紫外-可见光谱仪(UV-Vis)等手段进行了表征。结果表明,180℃时...采用溶剂热法在不同反应体系和温度下,制备了一系列Cu In S2(CIS)粉体。CIS粉体的物相、形貌、光吸收性能分别用X射线衍射(XRD)仪、场发射扫描电镜(FESEM)、透射电镜(TEM)、紫外-可见光谱仪(UV-Vis)等手段进行了表征。结果表明,180℃时乙醇-硫脲体系所得"绣球"状CIS粉体为黄铜矿结构,而乙二胺-硫化钠体系则为"花簇"状纤锌矿结构,升高溶剂热温度,两者形貌均往"球体"演变;结合XRD,差热(DSC)分析表明纤锌矿CIS具有往黄铜矿CIS转变的趋势,物相转变温度约为453℃;受物相转变影响,纤锌矿CIS的带隙值由黄铜矿的1.43 e V减小至1.35 e V,其可见光吸收能力增强。同时探讨了CIS物相的转变机理。展开更多
Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thi...Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thin CuInS_(2)nanosheets were prepared through a solvothermal method.Subsequently,metallic Ni was surface-modified onto CuInS_(2)through photo-deposition to serve as a co-catalyst.The optimized photocatalyst exhibited a hydrogen production rate of 15.5 mmol·g^(-1)·h^(-1)in water when used an ascorbic acid as hole scavenger,which is 9 times that of the original CuInS_(2).Transient absorption spectra(TAS)analysis demonstrates that the hole transfer from CuInS_(2)nanosheets to ascorbic acid,yielding a long-lived electron with a lifetime of 45.6μs.The electrons in CuInS_(2)are efficiently captured by Ni as active sites for driving hydrogen evolution.In situ TAS further indicates that ascorbic acid and Ni sites synergistically promote the electron transfer dynamics of CuInS_(2),achieving an electron transfer efficiency of 48.4%.This work provides a viable strategy for designing highly efficient photocatalysts with enhanced charge transfer.展开更多
Rational design of composite catalysts with efficient charge separation and transfer is of great significance to achieve efficient degradation of pollutants.Herein,CuInS_(2)nanoparticles are skillfully deposited on Ti...Rational design of composite catalysts with efficient charge separation and transfer is of great significance to achieve efficient degradation of pollutants.Herein,CuInS_(2)nanoparticles are skillfully deposited on TiO_(2)nanofibers through a hydrothermal method.The formation of S-scheme heterojunction is confirmed through free radical trapping experiments,in‐situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)measurements,density functional theory(DFT)calculations and femtosecond transient absorption spectroscopy(fs-TAS)results.These results reveal that the built-in electric field within the S-scheme heterojunction significantly enhances charge separation and transfer,boosting the catalyst's redox capabilities.The TiO_(2)/CuInS_(2)photocatalyst exhibits superior photocatalytic performance,achieving a degradation rate of 89%within 21 min of light irradiation,which is almost 2.2 times higher than that of TiO_(2).Additionally,the degradation products of TCH are investigated using in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and liquid chromatography–mass spectrometry(LC-MS),offering insights into the degradation pathway.This study highlights the potential advantage of ultrafast charge carrier transfer in S-scheme heterojunction,providing a promising strategy for designing high-efficiency photocatalytic systems for environmental remediation.The findings offer new directions for improving the degradation of persistent pollutants like tetracyclines.展开更多
CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth process.The as-obtained photocatalysts were explored by measuring their crystallinity,surface morp...CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth process.The as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption activity.The photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light respectively.The optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN itself.The enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional interface.This work is an effort to adjust CN-based polysulfide QD for speedy photocatalysis.The enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.展开更多
This paper demonstrates the design and fabrication of three-dimensional(3 D) hexagonally ordered microbowl arrays(MBAs) decorated with Cu In S2 nanosheets for enhanced photoelectrochemical(PEC) performance. The 3 D MB...This paper demonstrates the design and fabrication of three-dimensional(3 D) hexagonally ordered microbowl arrays(MBAs) decorated with Cu In S2 nanosheets for enhanced photoelectrochemical(PEC) performance. The 3 D MBAs are fabricated by a micro-fabrication technique. The ultrathin CuInS2 nanosheets are grown on the 3 D electrodes by solvothermal transformation of Cu film. The photocurrent density of 3 D photocathode(CuInS2@MBAs) is about two times higher than that of the planar counterpart(CuInS2@Planar). The improved PEC performance can be ascribed to the elevated light trapping ability and the increased surface area for loading photocatalysts. In addition, CdS quantum dots as cocatalysts are modified onto the Cu In S2 nanosheets to further enhance the PEC activity because the formed p-n heterojunction can accelerate the separation of photogenerated carriers. As a result, the 3 D photocathode of CuInS2/CdS@MBAs shows an optimal incident photon to current efficiency of 10% at the wavelength of400 nm. It is believed that this work can be generalized to design other hierarchical 3 D photoelectrodes for improved solar water splitting.展开更多
文摘采用溶剂热法在不同反应体系和温度下,制备了一系列Cu In S2(CIS)粉体。CIS粉体的物相、形貌、光吸收性能分别用X射线衍射(XRD)仪、场发射扫描电镜(FESEM)、透射电镜(TEM)、紫外-可见光谱仪(UV-Vis)等手段进行了表征。结果表明,180℃时乙醇-硫脲体系所得"绣球"状CIS粉体为黄铜矿结构,而乙二胺-硫化钠体系则为"花簇"状纤锌矿结构,升高溶剂热温度,两者形貌均往"球体"演变;结合XRD,差热(DSC)分析表明纤锌矿CIS具有往黄铜矿CIS转变的趋势,物相转变温度约为453℃;受物相转变影响,纤锌矿CIS的带隙值由黄铜矿的1.43 e V减小至1.35 e V,其可见光吸收能力增强。同时探讨了CIS物相的转变机理。
文摘Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thin CuInS_(2)nanosheets were prepared through a solvothermal method.Subsequently,metallic Ni was surface-modified onto CuInS_(2)through photo-deposition to serve as a co-catalyst.The optimized photocatalyst exhibited a hydrogen production rate of 15.5 mmol·g^(-1)·h^(-1)in water when used an ascorbic acid as hole scavenger,which is 9 times that of the original CuInS_(2).Transient absorption spectra(TAS)analysis demonstrates that the hole transfer from CuInS_(2)nanosheets to ascorbic acid,yielding a long-lived electron with a lifetime of 45.6μs.The electrons in CuInS_(2)are efficiently captured by Ni as active sites for driving hydrogen evolution.In situ TAS further indicates that ascorbic acid and Ni sites synergistically promote the electron transfer dynamics of CuInS_(2),achieving an electron transfer efficiency of 48.4%.This work provides a viable strategy for designing highly efficient photocatalysts with enhanced charge transfer.
基金financially supported by the National Natural Science Foundation of China(Nos.42207386,22378103,52372294,and 22262025)the Middle-aged and Young Teachers’Basic Ability Promotion Project of Guangxi(No.2021KY0390).
文摘Rational design of composite catalysts with efficient charge separation and transfer is of great significance to achieve efficient degradation of pollutants.Herein,CuInS_(2)nanoparticles are skillfully deposited on TiO_(2)nanofibers through a hydrothermal method.The formation of S-scheme heterojunction is confirmed through free radical trapping experiments,in‐situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)measurements,density functional theory(DFT)calculations and femtosecond transient absorption spectroscopy(fs-TAS)results.These results reveal that the built-in electric field within the S-scheme heterojunction significantly enhances charge separation and transfer,boosting the catalyst's redox capabilities.The TiO_(2)/CuInS_(2)photocatalyst exhibits superior photocatalytic performance,achieving a degradation rate of 89%within 21 min of light irradiation,which is almost 2.2 times higher than that of TiO_(2).Additionally,the degradation products of TCH are investigated using in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and liquid chromatography–mass spectrometry(LC-MS),offering insights into the degradation pathway.This study highlights the potential advantage of ultrafast charge carrier transfer in S-scheme heterojunction,providing a promising strategy for designing high-efficiency photocatalytic systems for environmental remediation.The findings offer new directions for improving the degradation of persistent pollutants like tetracyclines.
基金Foundation items:National Nature Science Foundation of China(50972107,51172165)Zhejinag Province Key Scientific and Technological Innovations Team of China(2009R50010)+1 种基金Key Foundation of Zhejiang Province Natural Science Foundation of China(Z4110347)Wenzhou Municipal Science and Technology Bureau Key Program(G20090082)
基金supported by National Natural Science Foundation of China(Nos.52272287,22268003 and 22202138)Project from Yunnan Province(Nos.202301AT070027,202305AF150116)Development Fund from Dali University(No.KY2296129740).
文摘CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth process.The as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption activity.The photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light respectively.The optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN itself.The enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional interface.This work is an effort to adjust CN-based polysulfide QD for speedy photocatalysis.The enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.
基金sponsored by the National Key Research and Development Program of China (2016YFA0200800)National Natural Science Foundation of China (61804156)Shanghai Sailing Program (18YF1427800)。
文摘This paper demonstrates the design and fabrication of three-dimensional(3 D) hexagonally ordered microbowl arrays(MBAs) decorated with Cu In S2 nanosheets for enhanced photoelectrochemical(PEC) performance. The 3 D MBAs are fabricated by a micro-fabrication technique. The ultrathin CuInS2 nanosheets are grown on the 3 D electrodes by solvothermal transformation of Cu film. The photocurrent density of 3 D photocathode(CuInS2@MBAs) is about two times higher than that of the planar counterpart(CuInS2@Planar). The improved PEC performance can be ascribed to the elevated light trapping ability and the increased surface area for loading photocatalysts. In addition, CdS quantum dots as cocatalysts are modified onto the Cu In S2 nanosheets to further enhance the PEC activity because the formed p-n heterojunction can accelerate the separation of photogenerated carriers. As a result, the 3 D photocathode of CuInS2/CdS@MBAs shows an optimal incident photon to current efficiency of 10% at the wavelength of400 nm. It is believed that this work can be generalized to design other hierarchical 3 D photoelectrodes for improved solar water splitting.