In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and exper...In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and experimental data have shown that the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure has a stronger light absorption capacity and larger specific surface area than pure g-C_(3)N_(4) NCs and g-C_(3)N_(4) nanosheets(NSs),and the presence of the co-catalysts 1T'-MoS_(2) can effectively inhibit the photoinduced carrier recombination.As a result,the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure with an optimum 1T'-MoS_(2) loading of 9 wt%displays a hydrogen evolution rate of 1949 mmol h^(-1) g^(-1),162.4,1.2,1.5,1.6 and 1.2 times than pure g-C_(3)N_(4) NCs(12 mmol h^(-1) g^(-1)),Pt/g-C_(3)N_(4) NCs(1615 mmol h^(-1) g^(-1))and Pt/g-C_(3)N_(4) nanosheets(NSs,1297 mmol h^(-1) g^(-1)),1T'-MoS_(2)/g-C_(3)N_(4) nanosheets(1216 mmol h^(-1) g^(-1))and 2H-MoS_(2)/g-C_(3)N_(4) nanocages(1573 mmol h^(-1) g^(-1)),respectively,and exhibits excellent cycle stability.Therefore,1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure is a suitable photocatalyst for green H_(2) production.展开更多
2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricte...2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricted by the recombination of photocarriers.We find that cobalt sulfide(CoS_(2))as a cocatalyst can promote g-C_(3)N_(4)nanosheets(NSs)to realize very efficient photocatalytic H_(2)generation.The prepared CoS_(2)/g-C_(3)N_(4)hybrids display highly boosted photocatalytic H_(2)generation performance and outstanding cycle stability.The optimized 7%-CoS_(2)/g-C_(3)N_(4)hybrids show a much improved photocatalytic H_(2)generation rate of 36.2μmol-1h-1,which is about 180 times as much as bare g-C_(3)N_(4)(0.2μmol-1h-1).In addition,the apparent quantum efficiency(AQE)of all the samples was computed under light atλ=370 nm,in which the AQE of 7%-CoS_(2)/g-C_(3)N_(4)hybrids is up to 5.72%.The experimental data and the DFT calculation suggest that the CoS_(2)/g-C_(3)N_(4)hybrid’s excellent HER activity is attributable to the lower overpotential and the smaller Co-H bond activation energy for HER.Accordingly,the CoS_(2)cocatalyst loading effectively boosts the photocatalytic performance of g-C_(3)N_(4)for H_(2)evolution.The project promotes fast development of high-efficiency photocatalysts and low-cost for photocatalytic H_(2)generation.展开更多
The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metall...The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metallic co-catalysts Ti3C2 MXene and metallic octahedral(1T)phase tungsten disulfide(WS2)act pathways transferring photoexcited electrons in assisting the photocatalytic H2 evolution.TiO2 nanosheets were in situ grown on highly conductive Ti3C2 MXenes and 1T-WS2 nanoparticles were then uniformly distributed on TiO2@Ti3C2 composite.Thus,a distinctive 1T-WS2@TiO2@Ti3C2 composite with double metallic co-catalysts was achieved,and the content of 1T phase reaches 73%.The photocatalytic H2 evolution performance of 1T-WS2@TiO2@Ti3C2 composite with an optimized 15 wt%WS2 ratio is nearly 50 times higher than that of TiO2 nanosheets because of conductive Ti3C2 MXene and 1T-WS2 resulting in the increase of electron transfer efficiency.Besides,the 1T-WS2 on the surface of TiO2@Ti3C2 composite enhances the Brunauer–Emmett–Teller surface area and boosts the density of active site.展开更多
TiO_(2)photocatalysts have been widely studied and applied for removing bacteria,but its antibacterial efficiency is limited to the ultraviolet(UV)range of the solar spectrum.In this work,we use the gold(Au)nanorods t...TiO_(2)photocatalysts have been widely studied and applied for removing bacteria,but its antibacterial efficiency is limited to the ultraviolet(UV)range of the solar spectrum.In this work,we use the gold(Au)nanorods to enhance the visible and near-infrared(NIR)light absorption of TiO_(2)NBs,a typical UV light photocatalyst,thus the enhancement of its full solar spectrum(UV,visible and NIR)photocatalytic antibacterial properties is achieved.Preliminary surface plasmon resonance(SPR)enhancement photocatalytic antibacterial mechanism is suggested.On one hand,transverse and longitudinal SPR of Au NRs is beneficial for visible and NIR light utilization.On the other hand,Au NRs combined with TiO_(2)NBs to form the heterostructure,which can improve the photogenerated carrier separation and direct electron transfer increases the hot electron concentration while Au NRs as the electron channel can well restrain charge recombination.finally produces the high yield of radical oxygen species and exhibits a superior antibacterial efficiency.Furthermore,we design a sterilization file cabinet with Au NR/TiO_(2)NB heterostructures as the photocatalytic coating plates.Our study reveals that Au NR/TiO_(2)NB heterostructure is a potential candidate for sterilization of bacteria and archives protection.展开更多
The porous few-layer g-C_(3)N_(4)(PFL-g-C_(3)N_(4))is prepared by a simple molecular self-assembly method.Compared with pure g-C_(3)N_(4),the as-prepared PFL-g-C_(3)N_(4) is ultrathin,the surface is rich in pores,and ...The porous few-layer g-C_(3)N_(4)(PFL-g-C_(3)N_(4))is prepared by a simple molecular self-assembly method.Compared with pure g-C_(3)N_(4),the as-prepared PFL-g-C_(3)N_(4) is ultrathin,the surface is rich in pores,and the photocatalytic nitrogen fixation activity is greatly increased to 8.20 mM h^(-1) gCat^(-1).Few-layer and ultrathin nature of PFL-g-C_(3)N_(4) can provide a larger specific surface area,expose more active sites,and reduce the diffusion path of charges and protons from the inside to the surface.In addition,the porous structure can narrow the band gap,thereby increasing the light absorption range and enhancing the light absorption capability.Meanwhile,the presence of nitrogen vacancies causes PFL-g-C_(3)N_(4) to move to a more negative conductive band value.More importantly,the isotopic experiments using ^(15)N_(2) as nitrogen source confirm the ammonia production originating from N2 rather than the decomposition of g-C_(3)N_(4).Therefore,PFL-g-C_(3)N_(4) can greatly improve the efficiency of visible light photocatalytic nitrogen fixation.展开更多
Recently,widespread attention has been devoted to the typical layered BiOCl or BiOBr because of the suitable nanostructure and band structure.However,owing to the fast carrier recombination,the photocatalytic performa...Recently,widespread attention has been devoted to the typical layered BiOCl or BiOBr because of the suitable nanostructure and band structure.However,owing to the fast carrier recombination,the photocatalytic performance of BiOX materials is not so satisfactory.Loading 1T phase WS_(2)nanosheets(NSs)onto Bi_(5)O_(7)Br NSs can improve the photocatalytic N_(2)fixation activity.Among these,the obtained 1T-WS_(2)@Bi_(5)O_(7)Br composites with optimum 5%1T-WS_(2)NSs display a significantly improved photocatalytic N_(2)fixation rate(8.43 mmol L^(−1)h^(−1)g^(−1)),2.51 times higher than pure Bi_(5)O_(7)Br(3.36 mmol L^(−1)h^(−1)g^(−1)).And the outstanding stability of 1T-WS_(2)@Bi_(5)O_(7)Br-5 composites is also achieved.Exactly,the photoexcited electrons from Bi_(5)O_(7)Br NSs are quickly transferred to conductive 1T phase WS_(2)as electron acceptors,which can promote the separation of carriers.In addition,1T-WS_(2)NSs can provide abundant active sites on the basal and edge planes,which can promote the efficiency of photocatalytic N_(2)fixation.This work offers a novel solution to improve the photocatalytic performance of Bi_(5)O_(7)Br NSs.展开更多
基金funding from the National Natural Science Foundation of China (No.51872173)Taishan Scholar Foundation of Shandong Province (No.tsqn201812068)+2 种基金Youth Innovation Technology Project of Higher School in Shandong Province (No.2019KJA013)Science and Technology Special Project of Qingdao City (No.20-3-4-3-nsh)the Opening Fund of State Key Laboratory of Heavy Oil Processing (No.SKLOP202002006)。
文摘In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and experimental data have shown that the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure has a stronger light absorption capacity and larger specific surface area than pure g-C_(3)N_(4) NCs and g-C_(3)N_(4) nanosheets(NSs),and the presence of the co-catalysts 1T'-MoS_(2) can effectively inhibit the photoinduced carrier recombination.As a result,the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure with an optimum 1T'-MoS_(2) loading of 9 wt%displays a hydrogen evolution rate of 1949 mmol h^(-1) g^(-1),162.4,1.2,1.5,1.6 and 1.2 times than pure g-C_(3)N_(4) NCs(12 mmol h^(-1) g^(-1)),Pt/g-C_(3)N_(4) NCs(1615 mmol h^(-1) g^(-1))and Pt/g-C_(3)N_(4) nanosheets(NSs,1297 mmol h^(-1) g^(-1)),1T'-MoS_(2)/g-C_(3)N_(4) nanosheets(1216 mmol h^(-1) g^(-1))and 2H-MoS_(2)/g-C_(3)N_(4) nanocages(1573 mmol h^(-1) g^(-1)),respectively,and exhibits excellent cycle stability.Therefore,1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure is a suitable photocatalyst for green H_(2) production.
基金funding from the National Natural Science Foundation of China(No.51872173 and 51772176)Taishan Scholar Foundation of Shandong Province(No.tsqn201812068 and tspd20161006)+2 种基金Youth Innovation Technology Project of Higher School in Shandong Province(No.2019KJA013)Science and Technology Special Project of Qingdao City(No.20-3-4-3-nsh)the Opening Fund of State Key Laboratory of Heavy Oil Processing(No.SKLOP202002006)。
文摘2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricted by the recombination of photocarriers.We find that cobalt sulfide(CoS_(2))as a cocatalyst can promote g-C_(3)N_(4)nanosheets(NSs)to realize very efficient photocatalytic H_(2)generation.The prepared CoS_(2)/g-C_(3)N_(4)hybrids display highly boosted photocatalytic H_(2)generation performance and outstanding cycle stability.The optimized 7%-CoS_(2)/g-C_(3)N_(4)hybrids show a much improved photocatalytic H_(2)generation rate of 36.2μmol-1h-1,which is about 180 times as much as bare g-C_(3)N_(4)(0.2μmol-1h-1).In addition,the apparent quantum efficiency(AQE)of all the samples was computed under light atλ=370 nm,in which the AQE of 7%-CoS_(2)/g-C_(3)N_(4)hybrids is up to 5.72%.The experimental data and the DFT calculation suggest that the CoS_(2)/g-C_(3)N_(4)hybrid’s excellent HER activity is attributable to the lower overpotential and the smaller Co-H bond activation energy for HER.Accordingly,the CoS_(2)cocatalyst loading effectively boosts the photocatalytic performance of g-C_(3)N_(4)for H_(2)evolution.The project promotes fast development of high-efficiency photocatalysts and low-cost for photocatalytic H_(2)generation.
基金fundings from the National Natural Science Foundation of China (Nos. 51872173 and 51772167)Taishan Scholarship of Young Scholars (No. tsqn201812068)+2 种基金Natural Science Foundation of Shandong Province (No. ZR2017JL020)Taishan Scholarship of Climbing Plan (No. tspd20161006)Key Research and Development Program of Shandong Province (No. 2018GGX102028)
文摘The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metallic co-catalysts Ti3C2 MXene and metallic octahedral(1T)phase tungsten disulfide(WS2)act pathways transferring photoexcited electrons in assisting the photocatalytic H2 evolution.TiO2 nanosheets were in situ grown on highly conductive Ti3C2 MXenes and 1T-WS2 nanoparticles were then uniformly distributed on TiO2@Ti3C2 composite.Thus,a distinctive 1T-WS2@TiO2@Ti3C2 composite with double metallic co-catalysts was achieved,and the content of 1T phase reaches 73%.The photocatalytic H2 evolution performance of 1T-WS2@TiO2@Ti3C2 composite with an optimized 15 wt%WS2 ratio is nearly 50 times higher than that of TiO2 nanosheets because of conductive Ti3C2 MXene and 1T-WS2 resulting in the increase of electron transfer efficiency.Besides,the 1T-WS2 on the surface of TiO2@Ti3C2 composite enhances the Brunauer–Emmett–Teller surface area and boosts the density of active site.
基金fundings from the National Natural Science Foundation of China(Nos.51872173,51772176)TaishanScholars Program of Shandong Province(Nos.tsqn201812068,tspd20161006)+6 种基金Higher School Youth Innovation Team of Shandong Province(No.2019KJA013)Key Research and Development Program of Shandong Province(No.2018GGX102028)Science and Technology Special Project of Qingdao City(No.20-3-4-3-nsh)the Opening Fund of State Key Laboratory of Heavy Oil Processing(No.SKLOP202002006)Cooperative Education Project of the Ministry of Education(No.201902195026)Humanities and Social Sciences Program(GoMoruo Studies)of the Education Department of Sichuan Province(No.GY2020C01)Shandong Archives Science and Technology Project(No.2020-33)。
文摘TiO_(2)photocatalysts have been widely studied and applied for removing bacteria,but its antibacterial efficiency is limited to the ultraviolet(UV)range of the solar spectrum.In this work,we use the gold(Au)nanorods to enhance the visible and near-infrared(NIR)light absorption of TiO_(2)NBs,a typical UV light photocatalyst,thus the enhancement of its full solar spectrum(UV,visible and NIR)photocatalytic antibacterial properties is achieved.Preliminary surface plasmon resonance(SPR)enhancement photocatalytic antibacterial mechanism is suggested.On one hand,transverse and longitudinal SPR of Au NRs is beneficial for visible and NIR light utilization.On the other hand,Au NRs combined with TiO_(2)NBs to form the heterostructure,which can improve the photogenerated carrier separation and direct electron transfer increases the hot electron concentration while Au NRs as the electron channel can well restrain charge recombination.finally produces the high yield of radical oxygen species and exhibits a superior antibacterial efficiency.Furthermore,we design a sterilization file cabinet with Au NR/TiO_(2)NB heterostructures as the photocatalytic coating plates.Our study reveals that Au NR/TiO_(2)NB heterostructure is a potential candidate for sterilization of bacteria and archives protection.
基金fundings from the National Natural Science Foundation of China(No.51872173 and 51772167)Taishan Scholarship of Young Scholars(No.tsqn201812068)+3 种基金Taishan Scholarship of Climbing Plan(No.tspd20161006)Key Research and Development Program of Shandong Province(No.2018GGX102028)Natural Science Foundation of Shandong Province(No.ZR2017JL020)Higher School Youth Innovation Team of Shandong Province(No.2019KJA013).
文摘The porous few-layer g-C_(3)N_(4)(PFL-g-C_(3)N_(4))is prepared by a simple molecular self-assembly method.Compared with pure g-C_(3)N_(4),the as-prepared PFL-g-C_(3)N_(4) is ultrathin,the surface is rich in pores,and the photocatalytic nitrogen fixation activity is greatly increased to 8.20 mM h^(-1) gCat^(-1).Few-layer and ultrathin nature of PFL-g-C_(3)N_(4) can provide a larger specific surface area,expose more active sites,and reduce the diffusion path of charges and protons from the inside to the surface.In addition,the porous structure can narrow the band gap,thereby increasing the light absorption range and enhancing the light absorption capability.Meanwhile,the presence of nitrogen vacancies causes PFL-g-C_(3)N_(4) to move to a more negative conductive band value.More importantly,the isotopic experiments using ^(15)N_(2) as nitrogen source confirm the ammonia production originating from N2 rather than the decomposition of g-C_(3)N_(4).Therefore,PFL-g-C_(3)N_(4) can greatly improve the efficiency of visible light photocatalytic nitrogen fixation.
基金funding from the National Natural Science Foundation of China(Nos.51872173 and 51772176)Taishan Scholars Program of Shandong Province(No.tsqn201812068)+1 种基金Higher School Youth Innovation Team of Shandong Province(No.2019KJA013)Science and Technology Special Project of Qingdao City(No.20-3-4-3-nsh).
文摘Recently,widespread attention has been devoted to the typical layered BiOCl or BiOBr because of the suitable nanostructure and band structure.However,owing to the fast carrier recombination,the photocatalytic performance of BiOX materials is not so satisfactory.Loading 1T phase WS_(2)nanosheets(NSs)onto Bi_(5)O_(7)Br NSs can improve the photocatalytic N_(2)fixation activity.Among these,the obtained 1T-WS_(2)@Bi_(5)O_(7)Br composites with optimum 5%1T-WS_(2)NSs display a significantly improved photocatalytic N_(2)fixation rate(8.43 mmol L^(−1)h^(−1)g^(−1)),2.51 times higher than pure Bi_(5)O_(7)Br(3.36 mmol L^(−1)h^(−1)g^(−1)).And the outstanding stability of 1T-WS_(2)@Bi_(5)O_(7)Br-5 composites is also achieved.Exactly,the photoexcited electrons from Bi_(5)O_(7)Br NSs are quickly transferred to conductive 1T phase WS_(2)as electron acceptors,which can promote the separation of carriers.In addition,1T-WS_(2)NSs can provide abundant active sites on the basal and edge planes,which can promote the efficiency of photocatalytic N_(2)fixation.This work offers a novel solution to improve the photocatalytic performance of Bi_(5)O_(7)Br NSs.
