Ni-based phosphides(NiPx)composed of earth-abundant elements are promising cocatalysts to replace noble metals for photocatalytic H2 evolution reaction(HER).A safe,energy-saving,and compositioncontrollable synthesis o...Ni-based phosphides(NiPx)composed of earth-abundant elements are promising cocatalysts to replace noble metals for photocatalytic H2 evolution reaction(HER).A safe,energy-saving,and compositioncontrollable synthesis of NiPx is still highly desired.A facile and mild solvothermal process was developed for the first time for selective synthesis of a series of NiPx,including Ni,Ni12P5,Ni2P/Ni12P5,Ni/Ni2P and Ni2P,through controlling the dosage of NaBH4 and NaH2PO2.The phosphidation process was mainly composed of(1)a sequential reduction of Ni2+to Nj0 and(H2PO2)-to P(around the formed Ni0)triggered by NaBH4,and(2)a final phosphidation between Nj0 and the in situ generated P atoms.The photocatalytic HER performance of g-C3N4 can be substantially improved with the decoration of NiPx(3 wt%)as the separation of photoinduced charge carriers can be promoted and some active sites with low over-potential for HER can be introduced.The cocatalytic efficiency of NiPx is mainly determined by P content.Ni2P with a high ratio of P consequently exhibits the highest HER performance(215.1 umol g-1 h-1),which is almost six times higher than that of the pristine g-C3N4(35.6 umol g-1 h-1).Thus,as for the cocatalyst based on Ni phosphides,Ni2P is the preferable crystal phase and more efforts should be devoted to Ni2P to further optimize its structure,texture,and morphology in future works.展开更多
CdS/graphtic carbon nitride (CdS/g-C3N4) hybrid materials were fabricated by thermal polymerization and hy- drothermal methods using Cd(CH3COO)2-2H2O, thioacetamide, and melamine as precursors. The structural and ...CdS/graphtic carbon nitride (CdS/g-C3N4) hybrid materials were fabricated by thermal polymerization and hy- drothermal methods using Cd(CH3COO)2-2H2O, thioacetamide, and melamine as precursors. The structural and op- tical properties of the as-synthesized samples were investigated by X-ray powder diffraction, UV-Vis diffuse reflec- tance spectroscopy, scanning electron microscopy, transmission electron microscopy, etc. A coupled system toward the selective oxidation of benzyl alcohol to benzaldehyde and the reduction of nitrobenzene into aniline was used to estimate the photocatalytic performance of CdS/g-C3N4 composite photocatalysts under visible light illumination. Results indicate that the CdS/g-C3N4 sample exhibits an outstanding photocatalytic performance for selective oxida- tion of benzyl alcohol and reduction of nitrobenzene. Meanwhile, benzotrifluoride is the best reaction medium among the screened solvents. Further research demonstrates that the selective oxidation of benzyl alcohol to ben- zaldehyde is induced by the photoexcited holes and the reduction of nitrobenzene into aniline is triggered by the photoexcited electrons. Additionally, the catalyst can be recycled several times without noticeable deactivation.展开更多
The significant increase of NO_(x)concentration causes severe damages to environment and human health.Light-driven photocatalytic technique affords an ideal solution for the removal of NO_(x)at ambient conditions.To e...The significant increase of NO_(x)concentration causes severe damages to environment and human health.Light-driven photocatalytic technique affords an ideal solution for the removal of NO_(x)at ambient conditions.To enhance the performance of NO_(x)removal,1D,2D and 3D photocatalysts have been constructed as the light absorption and the separation of charge carriers can be manipulated through controlling the morphology of the photocatalyst.Related works mainly focused on the construction and modification of special morphologic photocatalyst,including element doping,heterostructure constructing,crystal facet exposing,defect sites introducing and so on.Moreover,the excellent performance of the photocatalytic NO_(x)removal creates great awareness of the application,which has promising practical applications in NO_(x)removal by paint(removing NO_(x)indoor and outdoor)and pavement(degrading vehicle exhausts).For these considerations,recent advances in special morphologic photocatalysts for NO_(x)removal was summarized and commented in this review.The purpose is to provide insights into understanding the relationship between morphology and photocatalytic performance,meanwhile,to promote the application of photocatalytic technology in NO_(x)degradation.展开更多
基金financially supported by the Natural Science Foundation of Anhui Province for Distinguished Young Scholars(No.1808085J24)the Natural Science Foundation of Anhui Province(No.1808085MB45)+1 种基金the Natural Science Foundation of Educational Committee of Anhui Province(No.KJ2018A0671,KJ2018A0387)the National Natural Science Foundation of China(Nos.21473066,51772118,21603002)。
文摘Ni-based phosphides(NiPx)composed of earth-abundant elements are promising cocatalysts to replace noble metals for photocatalytic H2 evolution reaction(HER).A safe,energy-saving,and compositioncontrollable synthesis of NiPx is still highly desired.A facile and mild solvothermal process was developed for the first time for selective synthesis of a series of NiPx,including Ni,Ni12P5,Ni2P/Ni12P5,Ni/Ni2P and Ni2P,through controlling the dosage of NaBH4 and NaH2PO2.The phosphidation process was mainly composed of(1)a sequential reduction of Ni2+to Nj0 and(H2PO2)-to P(around the formed Ni0)triggered by NaBH4,and(2)a final phosphidation between Nj0 and the in situ generated P atoms.The photocatalytic HER performance of g-C3N4 can be substantially improved with the decoration of NiPx(3 wt%)as the separation of photoinduced charge carriers can be promoted and some active sites with low over-potential for HER can be introduced.The cocatalytic efficiency of NiPx is mainly determined by P content.Ni2P with a high ratio of P consequently exhibits the highest HER performance(215.1 umol g-1 h-1),which is almost six times higher than that of the pristine g-C3N4(35.6 umol g-1 h-1).Thus,as for the cocatalyst based on Ni phosphides,Ni2P is the preferable crystal phase and more efforts should be devoted to Ni2P to further optimize its structure,texture,and morphology in future works.
文摘CdS/graphtic carbon nitride (CdS/g-C3N4) hybrid materials were fabricated by thermal polymerization and hy- drothermal methods using Cd(CH3COO)2-2H2O, thioacetamide, and melamine as precursors. The structural and op- tical properties of the as-synthesized samples were investigated by X-ray powder diffraction, UV-Vis diffuse reflec- tance spectroscopy, scanning electron microscopy, transmission electron microscopy, etc. A coupled system toward the selective oxidation of benzyl alcohol to benzaldehyde and the reduction of nitrobenzene into aniline was used to estimate the photocatalytic performance of CdS/g-C3N4 composite photocatalysts under visible light illumination. Results indicate that the CdS/g-C3N4 sample exhibits an outstanding photocatalytic performance for selective oxida- tion of benzyl alcohol and reduction of nitrobenzene. Meanwhile, benzotrifluoride is the best reaction medium among the screened solvents. Further research demonstrates that the selective oxidation of benzyl alcohol to ben- zaldehyde is induced by the photoexcited holes and the reduction of nitrobenzene into aniline is triggered by the photoexcited electrons. Additionally, the catalyst can be recycled several times without noticeable deactivation.
基金supported by the National Natural Science Foundation of China(Nos.21607027,52002142,51772118,and 51972134)the Opening Project of Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3,No.FDLAP19007)+2 种基金and some Foundation of Anhui Province in China:Natural Science Foundation(Nos.1808085J24 and 2108085MB43)the University Natural Science Research Project(No.KJ2020A0126)the Cultivating Outstanding Talents(No.gxbjZD2020066).
文摘The significant increase of NO_(x)concentration causes severe damages to environment and human health.Light-driven photocatalytic technique affords an ideal solution for the removal of NO_(x)at ambient conditions.To enhance the performance of NO_(x)removal,1D,2D and 3D photocatalysts have been constructed as the light absorption and the separation of charge carriers can be manipulated through controlling the morphology of the photocatalyst.Related works mainly focused on the construction and modification of special morphologic photocatalyst,including element doping,heterostructure constructing,crystal facet exposing,defect sites introducing and so on.Moreover,the excellent performance of the photocatalytic NO_(x)removal creates great awareness of the application,which has promising practical applications in NO_(x)removal by paint(removing NO_(x)indoor and outdoor)and pavement(degrading vehicle exhausts).For these considerations,recent advances in special morphologic photocatalysts for NO_(x)removal was summarized and commented in this review.The purpose is to provide insights into understanding the relationship between morphology and photocatalytic performance,meanwhile,to promote the application of photocatalytic technology in NO_(x)degradation.