Molybdenum sulfides are promising electrocatalysts for the hydrogen evolution reaction(HER).Sand Mo‐related species have been proposed as the active site for forming adsorbed hydrogen to initiate the HER;however,the ...Molybdenum sulfides are promising electrocatalysts for the hydrogen evolution reaction(HER).Sand Mo‐related species have been proposed as the active site for forming adsorbed hydrogen to initiate the HER;however,the nature of the interaction between Mo centers and S ligands is unclear.Further,the development of cost‐effective water‐splitting systems using neutral water as a proton source for H2evolution is highly desirable,whereas the mechanism of the HER at neutral pH is rarely discussed.Here,the structural change in the Mo?Mo and S?S species in a synthesized molybdenum sulfide was monitored at neutral pH using in situ electrochemical Raman spectroscopy.Analysis of the potential dependent Raman spectra revealed that the band assigned to a terminal S?S species emerged along with synchronized changes in the frequency of the Mo?Mo,Mo3?μ3S,and Mo?S vibrational bands.This indicates that Mo?Mo bonds and terminal S?S ligands play synergistic roles in facilitating hydrogen evolution,likely via the internal reorganization of trinuclear Mo3?thio species.The nature and role of metal‐ligand interactions in the HER revealed in this study demonstrated a mechanism that is distinct from those reported previously in which the S or Mo sites function independently.展开更多
Atomic energy is an important part of current energy resources.Production of nuclear weapons and applications of nuclear fuels in nuclear power plants have accumulated numerous spent fuels containing238U compounds,whi...Atomic energy is an important part of current energy resources.Production of nuclear weapons and applications of nuclear fuels in nuclear power plants have accumulated numerous spent fuels containing238U compounds,which are critical nuclear materials.How to reduce the nuclear wastes and to make use of the spent uranium are key scientific issues of environmental and nuclear science.We have reviewed here the physiochemical properties and photocatalytic mechanisms of homogeneous and heterogeneous uranium-containing materials.The current research efforts demonstrate that spent fuels can become promising new photocatalytic materials.展开更多
文摘Molybdenum sulfides are promising electrocatalysts for the hydrogen evolution reaction(HER).Sand Mo‐related species have been proposed as the active site for forming adsorbed hydrogen to initiate the HER;however,the nature of the interaction between Mo centers and S ligands is unclear.Further,the development of cost‐effective water‐splitting systems using neutral water as a proton source for H2evolution is highly desirable,whereas the mechanism of the HER at neutral pH is rarely discussed.Here,the structural change in the Mo?Mo and S?S species in a synthesized molybdenum sulfide was monitored at neutral pH using in situ electrochemical Raman spectroscopy.Analysis of the potential dependent Raman spectra revealed that the band assigned to a terminal S?S species emerged along with synchronized changes in the frequency of the Mo?Mo,Mo3?μ3S,and Mo?S vibrational bands.This indicates that Mo?Mo bonds and terminal S?S ligands play synergistic roles in facilitating hydrogen evolution,likely via the internal reorganization of trinuclear Mo3?thio species.The nature and role of metal‐ligand interactions in the HER revealed in this study demonstrated a mechanism that is distinct from those reported previously in which the S or Mo sites function independently.
基金supported by the National Basic Research Program of China(973 Project,2011CB932400)Strategic International Collaborative Research Program of China(SICORP,2013DFG50150)
文摘Atomic energy is an important part of current energy resources.Production of nuclear weapons and applications of nuclear fuels in nuclear power plants have accumulated numerous spent fuels containing238U compounds,which are critical nuclear materials.How to reduce the nuclear wastes and to make use of the spent uranium are key scientific issues of environmental and nuclear science.We have reviewed here the physiochemical properties and photocatalytic mechanisms of homogeneous and heterogeneous uranium-containing materials.The current research efforts demonstrate that spent fuels can become promising new photocatalytic materials.