Renewable energy conversion as well as water electrolysis technologies are constrained by the fact that kinetics are always slow in the electrocatalytic oxygen evolution reaction(OER).There are numerous means and stra...Renewable energy conversion as well as water electrolysis technologies are constrained by the fact that kinetics are always slow in the electrocatalytic oxygen evolution reaction(OER).There are numerous means and strategies for the enhancement of OER activity.In this paper,we systematically review the important role of anionic vacancies in enhancing the OER activity of catalysts:increasing catalyst conductivity,improving electrical conductivity,and enhancing intermediate adsorption.In order to better detect the presence of vacancies in the samples,the principle of vacancy detection is reviewed in detail in terms of both spectroscopic and microscopic characterization,and the methods of vacancy formation as well as the factors influencing the concentration of vacancies are summarized in detail.In addition,the challenges and new directions for the study of anionic vacancies are provided.Lei Wang was awarded a Ph.D.in chemistry from Jilin University in 2006 under the supervision of Prof.Shouhua Feng.He worked as a Postdoctoral Scholar in Shandong University,the State Key Laboratory of Crystal Materials from 2008 to 2010.He is currently a professor at Qingdao University of Science and Technology.His research interests mainly focus on the design and synthesis of functional organic-inorganic hybrids and porous MOFs materials,as well as their applications in photocatalysis,electrocatalysis,lithium-ion battery,etc.Jingqi Chi received her B.S.degree and Ph.D.degree from the State Key Laboratory of Heavy Oil Processing,China University of Petroleum(East China).She is currently an associate professor at Qing dao University of Science and Technology.Her research interests focus on the design and synthesis of transition metal-based nanostructures and porous MOFs materials for electrochemical applications.展开更多
The development of metal sulfide catalysts with remarkable activity toward efficient overall photocatalytic water splitting remains challenging owing to the dominant charge recombination and deficient catalytic active...The development of metal sulfide catalysts with remarkable activity toward efficient overall photocatalytic water splitting remains challenging owing to the dominant charge recombination and deficient catalytic active sites.Moreover,in the process of water oxidation catalysis,the inhibition of severe photocorrosion is an immense task,requiring effective photogenic hole-transfer kinetics.Herein,stratified Co-MnO_(2)@CdS/CoS hollow cubes with spatially separated catalytic sites were rationally designed and fabricated as highly efficient controllable catalysts for photocatalytic overall water splitting.The unique self-templated method,including a continuous anion/cation-exchange reaction,integrates a Co-doped oxidation co-catalyst(Co-MnO_(2))and a reduction co-catalyst(CoS)on the nanocubes with uniform interface contact and ultrathin two-dimensional(2D)nanometer sheets.We demonstrate that the stratified Co-MnO_(2)@CdS/CoS hollow cubes can provide an abundance of active sites for surface redox reactions and contribute to the separation and migration of the photoionization charge carriers.In particular,CoS nanoparticles dispersed on the walls of CdS hollow cubes were identified as reduction co-catalysts accelerating hydrogen generation,while Co-MnO_(2) nanosheets attached to the inner walls of the CdS hollow cube were oxidation co-catalysts,promoting oxygen evolution dynamics.Benefiting from the desirable structural and compositional advantages,optimized stratification of Co-MnO_(2)@CdS/CoS nanocubes provided a catalytic system devoid of precious metals,which exhibited a remarkable overall photocatalytic water-splitting rate(735.4(H_(2))and 361.1(O_(2))μmol h^(−1) g^(−1)),being among the highest values reported thus far for CdS-based catalysts.Moreover,an apparent quantum efficiency(AQE)of 1.32%was achieved for hydrogen evolution at 420 nm.This study emphasizes the importance of rational design on the structure and composition of photocatalysts for overall water splitting.展开更多
文摘Renewable energy conversion as well as water electrolysis technologies are constrained by the fact that kinetics are always slow in the electrocatalytic oxygen evolution reaction(OER).There are numerous means and strategies for the enhancement of OER activity.In this paper,we systematically review the important role of anionic vacancies in enhancing the OER activity of catalysts:increasing catalyst conductivity,improving electrical conductivity,and enhancing intermediate adsorption.In order to better detect the presence of vacancies in the samples,the principle of vacancy detection is reviewed in detail in terms of both spectroscopic and microscopic characterization,and the methods of vacancy formation as well as the factors influencing the concentration of vacancies are summarized in detail.In addition,the challenges and new directions for the study of anionic vacancies are provided.Lei Wang was awarded a Ph.D.in chemistry from Jilin University in 2006 under the supervision of Prof.Shouhua Feng.He worked as a Postdoctoral Scholar in Shandong University,the State Key Laboratory of Crystal Materials from 2008 to 2010.He is currently a professor at Qingdao University of Science and Technology.His research interests mainly focus on the design and synthesis of functional organic-inorganic hybrids and porous MOFs materials,as well as their applications in photocatalysis,electrocatalysis,lithium-ion battery,etc.Jingqi Chi received her B.S.degree and Ph.D.degree from the State Key Laboratory of Heavy Oil Processing,China University of Petroleum(East China).She is currently an associate professor at Qing dao University of Science and Technology.Her research interests focus on the design and synthesis of transition metal-based nanostructures and porous MOFs materials for electrochemical applications.
文摘The development of metal sulfide catalysts with remarkable activity toward efficient overall photocatalytic water splitting remains challenging owing to the dominant charge recombination and deficient catalytic active sites.Moreover,in the process of water oxidation catalysis,the inhibition of severe photocorrosion is an immense task,requiring effective photogenic hole-transfer kinetics.Herein,stratified Co-MnO_(2)@CdS/CoS hollow cubes with spatially separated catalytic sites were rationally designed and fabricated as highly efficient controllable catalysts for photocatalytic overall water splitting.The unique self-templated method,including a continuous anion/cation-exchange reaction,integrates a Co-doped oxidation co-catalyst(Co-MnO_(2))and a reduction co-catalyst(CoS)on the nanocubes with uniform interface contact and ultrathin two-dimensional(2D)nanometer sheets.We demonstrate that the stratified Co-MnO_(2)@CdS/CoS hollow cubes can provide an abundance of active sites for surface redox reactions and contribute to the separation and migration of the photoionization charge carriers.In particular,CoS nanoparticles dispersed on the walls of CdS hollow cubes were identified as reduction co-catalysts accelerating hydrogen generation,while Co-MnO_(2) nanosheets attached to the inner walls of the CdS hollow cube were oxidation co-catalysts,promoting oxygen evolution dynamics.Benefiting from the desirable structural and compositional advantages,optimized stratification of Co-MnO_(2)@CdS/CoS nanocubes provided a catalytic system devoid of precious metals,which exhibited a remarkable overall photocatalytic water-splitting rate(735.4(H_(2))and 361.1(O_(2))μmol h^(−1) g^(−1)),being among the highest values reported thus far for CdS-based catalysts.Moreover,an apparent quantum efficiency(AQE)of 1.32%was achieved for hydrogen evolution at 420 nm.This study emphasizes the importance of rational design on the structure and composition of photocatalysts for overall water splitting.
