Layered double hydroxide(LDH)with special layered structure has been proved to have excellent hole transport capacity and good stability.Herein,we report a high efficient composite photocatalyst of CoAlLDH and BiPO4pr...Layered double hydroxide(LDH)with special layered structure has been proved to have excellent hole transport capacity and good stability.Herein,we report a high efficient composite photocatalyst of CoAlLDH and BiPO4prepared by hydrothermal and che mical adsorption(denoted as CoAl-LDH/BiPO_(4)).Phenol can be entirely degraded by 1%CoAl-LDH/BiPO_(4)under 30 min ultraviolet(UV)light irradiation,and the degradation rate constants k are 3 times and 39 times higher than that of pure BiPO_(4)and CoAl-LDH,respectively.The enhanced photocatalytic activity can be attributed to effective holes transfer from BiPO4to CoAl-LDH,which hinders the recombination of photo genera ted charge carriers.In addition,the combination of BiPO4and CoAl-LDH avoids the agglomeration of BiPO4and improves the stability of BiPO_(4).Active species capture experiments indicate that superoxide radicals(·O-_(2))are the main active species responsible for the degradation of phenol.This work provides technical approaches and research ideas for solving the photogenerated charge carrier recombination problem of photocatalyst.展开更多
Hematite(α-Fe_(2)O_(3))is a promising photoanode for photoelectrochemical(PEC)water splitting.However,the severe charge recombination and sluggish water oxidation kinetics extremely limit its use in photohydrogen con...Hematite(α-Fe_(2)O_(3))is a promising photoanode for photoelectrochemical(PEC)water splitting.However,the severe charge recombination and sluggish water oxidation kinetics extremely limit its use in photohydrogen conversion.Herein,a co-activation strategy is proposed,namely through phosphorus(P)doping and the loading of CoAl-layered double hydroxides(CoAl-LDHs)cocatalysts.Unexpectedly,the integrated system,CoAl-LDHs/P-Fe_(2)O_(3) photoanode,exhibits an outstanding photocurrent density of 1.56 mA/cm^(2) at 1.23 V(vs.reversible hydrogen electrode,RHE),under AM 1.5 G,which is 2.6 times of pureα-Fe_(2)O_(3).Systematic studies reveal that the remarkable PEC performance is attributed to accelerated surface OER kinetics and enhanced carrier separation efficiency.This work provides a feasible strategy to enhance the PEC performance of hematite photoanodes.展开更多
Hybrid materials are attracting intensive attention for their applications in electronics, photoelectronics, LEDs, field-effect transistors, etc. Engineering new hybrid materials and further exploiting their new funct...Hybrid materials are attracting intensive attention for their applications in electronics, photoelectronics, LEDs, field-effect transistors, etc. Engineering new hybrid materials and further exploiting their new functions will be significant for future science and technique development. In this work, alternatively stacked self-assembled CoAl LDH/MoS2 nanohybrid has been successfully synthesized by an exfoliation-flocculation method from positively charged CoAl LDH nanosheets（CoAl-NS） with negatively charged MoS2 nanosheets（MoS2-NS）. The CoAl LDH/MoS2 hybrid material exhibits an enhanced catalytic performance for oxygen evolution reaction（OER） compared with original constituents of CoAl LDH nanosheets and MoS2 nanosheets. The enhanced OER catalytic performance of CoAl LDH/MoS2 is demonstrated to be due to the improved electron transfer, more exposed catalytic active sites, and accelerated oxygen evolution reaction kinetics.展开更多
Reasonable design of heterojunction can greatly improve the photocatalytic hydrogen evolution activity of materials.Herein,p-n heterojunction of 2D/3D structure is constructed by the nanosheet of CoAl-LDH and rock-lik...Reasonable design of heterojunction can greatly improve the photocatalytic hydrogen evolution activity of materials.Herein,p-n heterojunction of 2D/3D structure is constructed by the nanosheet of CoAl-LDH and rock-like CuI.The introduction of CuI can make CoAl-LDH disperse better,which brings more reaction sites for the hydrogen evolution reaction.Meanwhile,the 2D/3D structure is conducive to the construction of p-n heterojunction between the CoAl-LDH and CuI.The optical and electrochemical properties of the material indicate that the separation and transference of photon-generated carriers are promoted by the p-n heterojunction.The activity of composite catalyst(CI-10)reaches a maximum of 3.59 mmol g^(−1) h^(−1) which is 28.5 times higher than that of CuI.Furthermore,the influence of the amount of CuI and pH value on the hydrogen evolution reaction is explored.Based on the band structures of CoAl-LDH and CuI,the mechanism of photocatalytic reaction of CI-10 is proposed.The p-n heterojunction constructed with the CuI as hole receptor provides a new way to enhance the activity of photocatalytic H_(2) evolution.展开更多
基金supported by the National Key Research and Development Program of China [2019YFC1904500]National Natural Science Foundation of China [52270115, 21878331, 21777080]Science Foundation of China University of Petroleum, Beijing [2462019QNXZ05, 2462020YXZZ018]
文摘Layered double hydroxide(LDH)with special layered structure has been proved to have excellent hole transport capacity and good stability.Herein,we report a high efficient composite photocatalyst of CoAlLDH and BiPO4prepared by hydrothermal and che mical adsorption(denoted as CoAl-LDH/BiPO_(4)).Phenol can be entirely degraded by 1%CoAl-LDH/BiPO_(4)under 30 min ultraviolet(UV)light irradiation,and the degradation rate constants k are 3 times and 39 times higher than that of pure BiPO_(4)and CoAl-LDH,respectively.The enhanced photocatalytic activity can be attributed to effective holes transfer from BiPO4to CoAl-LDH,which hinders the recombination of photo genera ted charge carriers.In addition,the combination of BiPO4and CoAl-LDH avoids the agglomeration of BiPO4and improves the stability of BiPO_(4).Active species capture experiments indicate that superoxide radicals(·O-_(2))are the main active species responsible for the degradation of phenol.This work provides technical approaches and research ideas for solving the photogenerated charge carrier recombination problem of photocatalyst.
基金supported by the National Natural Science Foundation of China(No.21575115)the Program for Chang Jiang Scholars and Innovative Research Team,Ministry of Education,China(No.IRT-16R61)。
文摘Hematite(α-Fe_(2)O_(3))is a promising photoanode for photoelectrochemical(PEC)water splitting.However,the severe charge recombination and sluggish water oxidation kinetics extremely limit its use in photohydrogen conversion.Herein,a co-activation strategy is proposed,namely through phosphorus(P)doping and the loading of CoAl-layered double hydroxides(CoAl-LDHs)cocatalysts.Unexpectedly,the integrated system,CoAl-LDHs/P-Fe_(2)O_(3) photoanode,exhibits an outstanding photocurrent density of 1.56 mA/cm^(2) at 1.23 V(vs.reversible hydrogen electrode,RHE),under AM 1.5 G,which is 2.6 times of pureα-Fe_(2)O_(3).Systematic studies reveal that the remarkable PEC performance is attributed to accelerated surface OER kinetics and enhanced carrier separation efficiency.This work provides a feasible strategy to enhance the PEC performance of hematite photoanodes.
基金financially supported by NNSFC(No.21025104,21271171,and 91022018)
文摘Hybrid materials are attracting intensive attention for their applications in electronics, photoelectronics, LEDs, field-effect transistors, etc. Engineering new hybrid materials and further exploiting their new functions will be significant for future science and technique development. In this work, alternatively stacked self-assembled CoAl LDH/MoS2 nanohybrid has been successfully synthesized by an exfoliation-flocculation method from positively charged CoAl LDH nanosheets（CoAl-NS） with negatively charged MoS2 nanosheets（MoS2-NS）. The CoAl LDH/MoS2 hybrid material exhibits an enhanced catalytic performance for oxygen evolution reaction（OER） compared with original constituents of CoAl LDH nanosheets and MoS2 nanosheets. The enhanced OER catalytic performance of CoAl LDH/MoS2 is demonstrated to be due to the improved electron transfer, more exposed catalytic active sites, and accelerated oxygen evolution reaction kinetics.
基金financially supported by the National Natural Science Foundation of China(22062001)。
文摘Reasonable design of heterojunction can greatly improve the photocatalytic hydrogen evolution activity of materials.Herein,p-n heterojunction of 2D/3D structure is constructed by the nanosheet of CoAl-LDH and rock-like CuI.The introduction of CuI can make CoAl-LDH disperse better,which brings more reaction sites for the hydrogen evolution reaction.Meanwhile,the 2D/3D structure is conducive to the construction of p-n heterojunction between the CoAl-LDH and CuI.The optical and electrochemical properties of the material indicate that the separation and transference of photon-generated carriers are promoted by the p-n heterojunction.The activity of composite catalyst(CI-10)reaches a maximum of 3.59 mmol g^(−1) h^(−1) which is 28.5 times higher than that of CuI.Furthermore,the influence of the amount of CuI and pH value on the hydrogen evolution reaction is explored.Based on the band structures of CoAl-LDH and CuI,the mechanism of photocatalytic reaction of CI-10 is proposed.The p-n heterojunction constructed with the CuI as hole receptor provides a new way to enhance the activity of photocatalytic H_(2) evolution.
