Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely bee...Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely been produced through the modulation of their structure and composition.In this study,a series of bimetallic nickel-iron phosphide(Ni_(x)Fe_(2-x)P,where 0<x<2)cocatalysts with controllable structures and overpotentials were designed by adjusting the atomic ratio of Ni/Fe onto nonmetallic elemental red phosphorus(RP)for the photocatalytic selective oxidation of benzyl alcohol(BA)coupled with hydrogen production.The catalysts exhibited an outstanding photocatalytic activity for benzaldehyde and a high H_(2)yield.The RP regulated by bimetallic phosphide cocatalysts(Ni_(x)Fe_(2-x)P)demonstrated higher photocatalytic oxidation-reduction activity than that regulated by monometallic phosphide cocatalysts(Ni_(2)P and Fe2P).In particular,the RP regulated by Ni_(1.25)Fe_(0.75)P exhibited the best photocatalytic performance.In addition,experimental and theoretical calculations further illustrated that Ni_(1.25)Fe_(0.75)P,with the optimized electronic structure,possessed good electrical conductivity and provided strong adsorption and abundant active sites,thereby accelerating electron migration and lowering the reaction energy barrier of RP.This finding offers valuable insights into the rational design of highly effective cocatalysts aimed at optimizing the photocatalytic activity of composite photocatalysts.展开更多
Photocatalysts are essential for the preparation of wanted fine chemical and biomedical intermediates via visible photocatalysis,but existing photocatalysts with low catalytic efficiency limit their wide applications....Photocatalysts are essential for the preparation of wanted fine chemical and biomedical intermediates via visible photocatalysis,but existing photocatalysts with low catalytic efficiency limit their wide applications.Herein,CdS/Ti_(3)C2T_(x)/MBI nanocomposites have been successfully fabricated through anchoring reduction cocatalyst Ti_(3)C_(2)T_(x) with electron-drawing ability and oxidation cocatalyst 2-mercaptobenzimidazole(MBI)with hole-capturing capacity on CdS nanoparticles.The Ti_(3)C_(2)T_(x) and MBI of CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites can extract electrons and holes from CdS nanoparticles to come true electron-hole separation,respectively.Moreover,the electron-drawing and hole-capturing abilities of the CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites depend on Ti_(3)C_(2)T_(x) and MBI contents,and the quantifiable electron and hole transfers finally determine photocatalytic efficiency of the CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites.The transient photocurrent density of the CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites is 6-fold higher than that of the CdS nanoparticles.The CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites with strong electron-hole separation capability exhibit outstanding visible photocatalytic organic transformation properties.The CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites produce(E)-N-benzyl-1-phenylmethylimine in~96%yield(~8000μmol·g^(-1)·h^(-1)),which is 3-fold higher than the CdS nanoparticles(~2500μmol·g^(-1)·h^(-1),30%).This work provides a new strategy for constructing efficient and stable photocatalysts that can be used for efficient visible light-driven organic transformations.展开更多
Negatively charged open-framework metal sulfides(NOSs),taking advantages of the characteristics of excellent visible light absorption,easily exchanged cations,and abundant active sites,hold significant promise as high...Negatively charged open-framework metal sulfides(NOSs),taking advantages of the characteristics of excellent visible light absorption,easily exchanged cations,and abundant active sites,hold significant promise as highly efficient photocatalysts for hydrogen evolution.However,their applications in photocatalytic hydrogen evolution(PHE)are infrequently documented and the corresponding photocatalytic mechanism has not yet been explored.Herein,we excavated a novel NOS photocatalyst of(Me_(2)NH_(2))_(6)In_(10)S_(18)(MIS)with a three-dimensional(3D)structure,and successfully incorporated divalent Co(Ⅱ)and metal Co(0)into its cavities via the convenient cation exchange-assisted approach to regulate the critical steps of photocatalytic reactions.As the introduced Co(0)allows for more efficient light utilization and adroitly surficial hydrogen desorption,and meanwhile acts as the‘electron pump’for rapid charge transfer,Co(0)-modified MIS delivers a surprising PHE activity in the initial stage of photocatalysis.With the prolonging of illumination,metal Co(0)gradually escapes from MIS framework,resulting in the decline of PHE performance.By stark contrast,the incorporated Co(Ⅱ)can establish a strong interaction with MIS framework,and simultaneously capture photogenerated electrons from MIS to produce Co(0),which constructs a stable photocatalytic system as well as provides additional channels for spatially separating photogenerated carriers.Thus,Co(Ⅱ)-modified MIS exhibits a robust and highly stable PHE activity of~4944μmol/g/h during the long-term photocatalytic reactions,surpassing most of the previously reported In–S framework photocatalysts.This work represents a breakthrough in the study of PHE performance and mechanism of NOS-based photocatalysts,and sheds light on the design of vip confined NOS-based photocatalysts towards high-efficiency solar-to-chemical energy conversion.展开更多
BiVO_(4)is an ideal photocatalysts for H_(2)O_(2)generation due to its suitable band edge.In practice,however,the photocatalytic performance of BiVO_(4)is substantially low owing to the slow kinetics of 2e^(-)O_(2)red...BiVO_(4)is an ideal photocatalysts for H_(2)O_(2)generation due to its suitable band edge.In practice,however,the photocatalytic performance of BiVO_(4)is substantially low owing to the slow kinetics of 2e^(-)O_(2)reduction(2e^(-)ORR)and water oxidation(WOR)processes.To solve the problems,in this work,the AuPd alloy cocatalyst and the NiOOH cocatalys were modified on the electron(010)facets and the(110)hole facet of BiVO_(4)by photodeposition method.The designed AuPd/BiVO_(4)/NiOOH(0.5%)photocatalyst showed prominent photocatalytic H_(2)O_(2)production activity of 289.3μmmol_·L^(-1)with an AQE value of 0.89%at 420 nm,which was increased by 40 times compared with the BiVO_(4)sample(7.1μmmol_?L^(-1)).The outstanding photocatalytic activity of the AuPd/BiVO_(4)/NiOOH photocatalyst can be attributed to the synergistic effect of AuPd and NiOOH cocatalysts,which promoted the kinetics of oxygen reduction and water oxidation,and concurrently facilitated the charge separation.The present strategy of dual-cocatalyst rational assembly on different facets of BiVO_(4)provides an insight into explore efficient BiVO_(4)-based materials for H_(2)O_(2)production.展开更多
文摘Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely been produced through the modulation of their structure and composition.In this study,a series of bimetallic nickel-iron phosphide(Ni_(x)Fe_(2-x)P,where 0<x<2)cocatalysts with controllable structures and overpotentials were designed by adjusting the atomic ratio of Ni/Fe onto nonmetallic elemental red phosphorus(RP)for the photocatalytic selective oxidation of benzyl alcohol(BA)coupled with hydrogen production.The catalysts exhibited an outstanding photocatalytic activity for benzaldehyde and a high H_(2)yield.The RP regulated by bimetallic phosphide cocatalysts(Ni_(x)Fe_(2-x)P)demonstrated higher photocatalytic oxidation-reduction activity than that regulated by monometallic phosphide cocatalysts(Ni_(2)P and Fe2P).In particular,the RP regulated by Ni_(1.25)Fe_(0.75)P exhibited the best photocatalytic performance.In addition,experimental and theoretical calculations further illustrated that Ni_(1.25)Fe_(0.75)P,with the optimized electronic structure,possessed good electrical conductivity and provided strong adsorption and abundant active sites,thereby accelerating electron migration and lowering the reaction energy barrier of RP.This finding offers valuable insights into the rational design of highly effective cocatalysts aimed at optimizing the photocatalytic activity of composite photocatalysts.
文摘Photocatalysts are essential for the preparation of wanted fine chemical and biomedical intermediates via visible photocatalysis,but existing photocatalysts with low catalytic efficiency limit their wide applications.Herein,CdS/Ti_(3)C2T_(x)/MBI nanocomposites have been successfully fabricated through anchoring reduction cocatalyst Ti_(3)C_(2)T_(x) with electron-drawing ability and oxidation cocatalyst 2-mercaptobenzimidazole(MBI)with hole-capturing capacity on CdS nanoparticles.The Ti_(3)C_(2)T_(x) and MBI of CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites can extract electrons and holes from CdS nanoparticles to come true electron-hole separation,respectively.Moreover,the electron-drawing and hole-capturing abilities of the CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites depend on Ti_(3)C_(2)T_(x) and MBI contents,and the quantifiable electron and hole transfers finally determine photocatalytic efficiency of the CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites.The transient photocurrent density of the CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites is 6-fold higher than that of the CdS nanoparticles.The CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites with strong electron-hole separation capability exhibit outstanding visible photocatalytic organic transformation properties.The CdS/Ti_(3)C_(2)T_(x)/MBI nanocomposites produce(E)-N-benzyl-1-phenylmethylimine in~96%yield(~8000μmol·g^(-1)·h^(-1)),which is 3-fold higher than the CdS nanoparticles(~2500μmol·g^(-1)·h^(-1),30%).This work provides a new strategy for constructing efficient and stable photocatalysts that can be used for efficient visible light-driven organic transformations.
基金financial supports provided by the Natural Science Foundation of Fujian Province(No.2024J01195)the National Nature Science Foundation of China(No.21905279)+1 种基金Sanming University(Nos.22YG11 and PYT2201)the Education Scientific Research Project of Youth Teachers in the Education Department of Fujian Province(No.JAT220351).
文摘Negatively charged open-framework metal sulfides(NOSs),taking advantages of the characteristics of excellent visible light absorption,easily exchanged cations,and abundant active sites,hold significant promise as highly efficient photocatalysts for hydrogen evolution.However,their applications in photocatalytic hydrogen evolution(PHE)are infrequently documented and the corresponding photocatalytic mechanism has not yet been explored.Herein,we excavated a novel NOS photocatalyst of(Me_(2)NH_(2))_(6)In_(10)S_(18)(MIS)with a three-dimensional(3D)structure,and successfully incorporated divalent Co(Ⅱ)and metal Co(0)into its cavities via the convenient cation exchange-assisted approach to regulate the critical steps of photocatalytic reactions.As the introduced Co(0)allows for more efficient light utilization and adroitly surficial hydrogen desorption,and meanwhile acts as the‘electron pump’for rapid charge transfer,Co(0)-modified MIS delivers a surprising PHE activity in the initial stage of photocatalysis.With the prolonging of illumination,metal Co(0)gradually escapes from MIS framework,resulting in the decline of PHE performance.By stark contrast,the incorporated Co(Ⅱ)can establish a strong interaction with MIS framework,and simultaneously capture photogenerated electrons from MIS to produce Co(0),which constructs a stable photocatalytic system as well as provides additional channels for spatially separating photogenerated carriers.Thus,Co(Ⅱ)-modified MIS exhibits a robust and highly stable PHE activity of~4944μmol/g/h during the long-term photocatalytic reactions,surpassing most of the previously reported In–S framework photocatalysts.This work represents a breakthrough in the study of PHE performance and mechanism of NOS-based photocatalysts,and sheds light on the design of vip confined NOS-based photocatalysts towards high-efficiency solar-to-chemical energy conversion.
基金Funded by the National Natural Science Foundation of China(Nos.22178276,22178275,U22A20147,and 22075220)the Natural Science Foundation of Hubei Province of China(No.2022CFA001)。
文摘BiVO_(4)is an ideal photocatalysts for H_(2)O_(2)generation due to its suitable band edge.In practice,however,the photocatalytic performance of BiVO_(4)is substantially low owing to the slow kinetics of 2e^(-)O_(2)reduction(2e^(-)ORR)and water oxidation(WOR)processes.To solve the problems,in this work,the AuPd alloy cocatalyst and the NiOOH cocatalys were modified on the electron(010)facets and the(110)hole facet of BiVO_(4)by photodeposition method.The designed AuPd/BiVO_(4)/NiOOH(0.5%)photocatalyst showed prominent photocatalytic H_(2)O_(2)production activity of 289.3μmmol_·L^(-1)with an AQE value of 0.89%at 420 nm,which was increased by 40 times compared with the BiVO_(4)sample(7.1μmmol_?L^(-1)).The outstanding photocatalytic activity of the AuPd/BiVO_(4)/NiOOH photocatalyst can be attributed to the synergistic effect of AuPd and NiOOH cocatalysts,which promoted the kinetics of oxygen reduction and water oxidation,and concurrently facilitated the charge separation.The present strategy of dual-cocatalyst rational assembly on different facets of BiVO_(4)provides an insight into explore efficient BiVO_(4)-based materials for H_(2)O_(2)production.
