A simple two-step hydrothermal method synthesized four different CdS/Fe_(3)O_(4)photocatalysts with varying ratios of mass of CdS to Fe_(3)O_(4).The composition and morphology of the prepared samples were investigated...A simple two-step hydrothermal method synthesized four different CdS/Fe_(3)O_(4)photocatalysts with varying ratios of mass of CdS to Fe_(3)O_(4).The composition and morphology of the prepared samples were investigated using X-ray diffraction(XRD),Raman spectrum,X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).Solid UV reflectance spectra testing found that CdS/Fe_(3)O_(4)nanocomposites had good light absorption throughout the spectral range,promoting their photocatalytic properties.Under visible light irradiation,CdS/Fe_(3)O_(4)(2∶5)with a mass ratio of 2∶5 exhibited excellent photocatalytic perfor-mance,with a degradation rate of 98.8%for rhodamine B.Furthermore,after five cycles of photocatalytic degrada-tion reaction,the rhodamine B degradation rate remained at 96.2%,indicating that the photocatalysts have good pho-tocatalytic stability.展开更多
The appropriate regulation of band structure is an effective strategy in constructing efficient photocatalytic systems.Present photocatalytic system mainly employs powder photocatalysts,which makes their recovery reli...The appropriate regulation of band structure is an effective strategy in constructing efficient photocatalytic systems.Present photocatalytic system mainly employs powder photocatalysts,which makes their recovery reliant on expensive separation processes and severely limits their industrial application.Herein,we constructed a novel CdS/Ni_(3)S_(2)heterostructure using free-standing and flexible nickel fiber paper as the matrix.The regulated energy band structure achieves effective electron–hole separation.The as-synthesized flexible photocatalyst exhibits considerable photocatalytic activity toward the H_(2)evolution reaction under visible-light irradiation,with an H_(2)production rate of5.63μmol·cm^(-2)·h^(-1)(14.1 mmol·g^(-1)cat·h^(-1)according to the catalyst loading content).Additionally,the otherwisewasted excited holes simultaneously drive organic transformations to yield value-added organic products,thus markedly improving the photocatalytic H_(2)evolution rate.Such a photocatalytic system is scaled up further,where a self-supported 20 cm×25 cm sample achieves a champion H_(2)production rate of 60-80μmol·h^(-1)under practical sun irradiation.This newly developed self-supported photocatalyst produces opportunities for practical solar H2production with biomass upgrading.展开更多
The charge carrier separation efficiency and the adsorption capacity of the photocatalyst usually affect the degradation rate of antibiotics.Herein,Cerium-doped leaf-like CdS(Ce-CdS)modified with ultrathin N-doped rGO...The charge carrier separation efficiency and the adsorption capacity of the photocatalyst usually affect the degradation rate of antibiotics.Herein,Cerium-doped leaf-like CdS(Ce-CdS)modified with ultrathin N-doped rGO(N-rGO)composites were successfully constructed(Ce-CdS/N-rGO)to investigate the removal efficiency of tetracycline(TC).X-ray photoelectron spectroscopy(XPS)and photoelectrochemical results revealed that Ce ions doped in CdS acting as the electron capture sites facilitated the interfacial charge transfer.Theoretical calculation(DFT)results indicated that the interfacial effect between Ce-CdS and ultrathin N-rGO promoted the transfer of photogenerated electrons under the synergistic effect between the doping and interface modification strategy.The optimized Ce5-CdS/N-rGO20 composites had the maximum TC removal capability(94.5%)and maintained a stable cycling performance.In addition,the adsorption-driven photocatalytic degradation pathway of TC was studied through mass spectrometry(MS)and in-situ Fourier transform infrared spectroscopy(in-situ FTIR).This study will provide an effective strategy for the construction of efficient photocatalytic composites for wastewater treatment.展开更多
Construction of heterojunctions is a normal and effective strategy to improve the photocatalytic performances of semiconductors,through which both the lifetime and the redox ability of electrons/holes can be improved,...Construction of heterojunctions is a normal and effective strategy to improve the photocatalytic performances of semiconductors,through which both the lifetime and the redox ability of electrons/holes can be improved,as co mpared to the respective component.On this basis,we constructed Z-scheme CdS/LaFeO_(3) heterojunctions(CdS/LFO),by in-situ growing different amounts of CdS on the surface of LaFeO_(3),for photocatalytic degradation of tetracycline hydrochloride(TC)in aqueous solution at room temperature.The crystal structure,surface morphology and optoelectronic properties of the COS/LFO heterojunctions were systemically characterized to correlate the reaction activity.Photocatalytic tests indicate that the CdS/LFO heterojunctions exhibit promising activity for TC degradation under visible light irradiation(λ≥420 nm),with 85%TC conversion obtained at reaction time of 45 min,which is 3.4 and 1.9 times higher than that of CdS and LaFeO_(3).The CdS/LFO heterojunctions are also stable in the reaction and can be reused for four cycles with no appreciable activity loss.The applicability of CdS/LFO to photocatalytic degradation of organic dyes,as well as the reaction mechanism,was also explored.展开更多
文摘A simple two-step hydrothermal method synthesized four different CdS/Fe_(3)O_(4)photocatalysts with varying ratios of mass of CdS to Fe_(3)O_(4).The composition and morphology of the prepared samples were investigated using X-ray diffraction(XRD),Raman spectrum,X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).Solid UV reflectance spectra testing found that CdS/Fe_(3)O_(4)nanocomposites had good light absorption throughout the spectral range,promoting their photocatalytic properties.Under visible light irradiation,CdS/Fe_(3)O_(4)(2∶5)with a mass ratio of 2∶5 exhibited excellent photocatalytic perfor-mance,with a degradation rate of 98.8%for rhodamine B.Furthermore,after five cycles of photocatalytic degrada-tion reaction,the rhodamine B degradation rate remained at 96.2%,indicating that the photocatalysts have good pho-tocatalytic stability.
基金supported by the National Natural Science Foundation of China(Nos.51972147,52022037 and 52202366)Taishan Scholars Project Special Funds(No.tsqn201812083),the Innovative Team Project of Jinan(No.2021GXRC019)+1 种基金the Natural Science Foundation of Shandong Province(Nos.ZR2019YQ20,ZR2021QE011,ZR2021JQ15 and ZR2022YQ42)the King Abdullah University of Science and Technology(KAUST)。
文摘The appropriate regulation of band structure is an effective strategy in constructing efficient photocatalytic systems.Present photocatalytic system mainly employs powder photocatalysts,which makes their recovery reliant on expensive separation processes and severely limits their industrial application.Herein,we constructed a novel CdS/Ni_(3)S_(2)heterostructure using free-standing and flexible nickel fiber paper as the matrix.The regulated energy band structure achieves effective electron–hole separation.The as-synthesized flexible photocatalyst exhibits considerable photocatalytic activity toward the H_(2)evolution reaction under visible-light irradiation,with an H_(2)production rate of5.63μmol·cm^(-2)·h^(-1)(14.1 mmol·g^(-1)cat·h^(-1)according to the catalyst loading content).Additionally,the otherwisewasted excited holes simultaneously drive organic transformations to yield value-added organic products,thus markedly improving the photocatalytic H_(2)evolution rate.Such a photocatalytic system is scaled up further,where a self-supported 20 cm×25 cm sample achieves a champion H_(2)production rate of 60-80μmol·h^(-1)under practical sun irradiation.This newly developed self-supported photocatalyst produces opportunities for practical solar H2production with biomass upgrading.
基金financially supported by the National Natural Science Foundation of China(Nos.22078131 and 22108102)The Science and Technology Planning Social Development Project of Zhenjiang City(No.SH2021013)+1 种基金The Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.21KJB430036)The Jiangsu Provincial Founds for Young Scholars(No.BK20210782).
文摘The charge carrier separation efficiency and the adsorption capacity of the photocatalyst usually affect the degradation rate of antibiotics.Herein,Cerium-doped leaf-like CdS(Ce-CdS)modified with ultrathin N-doped rGO(N-rGO)composites were successfully constructed(Ce-CdS/N-rGO)to investigate the removal efficiency of tetracycline(TC).X-ray photoelectron spectroscopy(XPS)and photoelectrochemical results revealed that Ce ions doped in CdS acting as the electron capture sites facilitated the interfacial charge transfer.Theoretical calculation(DFT)results indicated that the interfacial effect between Ce-CdS and ultrathin N-rGO promoted the transfer of photogenerated electrons under the synergistic effect between the doping and interface modification strategy.The optimized Ce5-CdS/N-rGO20 composites had the maximum TC removal capability(94.5%)and maintained a stable cycling performance.In addition,the adsorption-driven photocatalytic degradation pathway of TC was studied through mass spectrometry(MS)and in-situ Fourier transform infrared spectroscopy(in-situ FTIR).This study will provide an effective strategy for the construction of efficient photocatalytic composites for wastewater treatment.
基金Project supported by the National Natural Science Foundation of China(21976141,42277485)the Department of Science and Technology of Hubei Province(2021CFA034)+1 种基金the Department of Education of Hubei Province(T2020011)the Opening Project of Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing(STRZ202202)。
文摘Construction of heterojunctions is a normal and effective strategy to improve the photocatalytic performances of semiconductors,through which both the lifetime and the redox ability of electrons/holes can be improved,as co mpared to the respective component.On this basis,we constructed Z-scheme CdS/LaFeO_(3) heterojunctions(CdS/LFO),by in-situ growing different amounts of CdS on the surface of LaFeO_(3),for photocatalytic degradation of tetracycline hydrochloride(TC)in aqueous solution at room temperature.The crystal structure,surface morphology and optoelectronic properties of the COS/LFO heterojunctions were systemically characterized to correlate the reaction activity.Photocatalytic tests indicate that the CdS/LFO heterojunctions exhibit promising activity for TC degradation under visible light irradiation(λ≥420 nm),with 85%TC conversion obtained at reaction time of 45 min,which is 3.4 and 1.9 times higher than that of CdS and LaFeO_(3).The CdS/LFO heterojunctions are also stable in the reaction and can be reused for four cycles with no appreciable activity loss.The applicability of CdS/LFO to photocatalytic degradation of organic dyes,as well as the reaction mechanism,was also explored.
