Hydrogen energy carrier produced by water electrolysis in alkaline electrolytes is rather meaningful and significant for global sustainability imperatives,while the highpH condition usually leads to a poor reversibili...Hydrogen energy carrier produced by water electrolysis in alkaline electrolytes is rather meaningful and significant for global sustainability imperatives,while the highpH condition usually leads to a poor reversibility of proton adsorption and desorption that significantly determines the hydrogen-generation activity in hydrogen evolution reaction(HER)process.Herein,we demonstrate a remarkable Ru-Mo solid-solution nanocrystal catalyst in alkaline HER process by a very simple but feasible pyrolysis and alkali leaching strategy.Benefiting from the pinning effect and local chemical-and electronic-structure regulations of Mo solute atoms,an ultra-low overpotential(17.3 mV)and an exceptional stability(>100 h)at the typical current density of 10 mA·cm^(−2)are achieved on the ultrasmall Ru-Mo solid-solution nanocrystal catalyst in 1.0 M KOH electrolyte.Density function theory(DFT)calculations gain an insight into the synergistic effect of neighboring Ru and Mo sites in alkaline HER process,where Mo solute atoms are beneficial for the adsorption and activation of water molecules for proton generation and accumulation due to their rich outermost 4d vacant orbitals,while the energy-favorable Ru sites are responsible for the fast deprotonation kinetics of hydrogen intermediates.Our work may provide an interesting route for the development of efficient and stable solid-solution alloy nanocrystals towards alkaline water electrolysis and beyond.展开更多
The effect of addition of Ru and Pd to Mo/HZSM-5 catalysts used in the dehydroaromatization of methane was investigated. Catalytic tests and temperature-programmed oxidation results showed that Pd-based catalysts were...The effect of addition of Ru and Pd to Mo/HZSM-5 catalysts used in the dehydroaromatization of methane was investigated. Catalytic tests and temperature-programmed oxidation results showed that Pd-based catalysts were more selective to naphthalene and suffered strong deactivation. The presence of Ru improved the activity and stability, with a decrease in the carbonaceous deposit probably because of a mechanism of protection of the Mo2C surface.展开更多
基金supports from the National Natural Science Foundation of China(No.22109171)the Chongqing Talent Program(No.cstc2024ycjh-bgzxm0068))+1 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJZD-K202301101)the Natural Science Foundation of Chongqing(No.CSTB2023NSCQ-MSX0315).
文摘Hydrogen energy carrier produced by water electrolysis in alkaline electrolytes is rather meaningful and significant for global sustainability imperatives,while the highpH condition usually leads to a poor reversibility of proton adsorption and desorption that significantly determines the hydrogen-generation activity in hydrogen evolution reaction(HER)process.Herein,we demonstrate a remarkable Ru-Mo solid-solution nanocrystal catalyst in alkaline HER process by a very simple but feasible pyrolysis and alkali leaching strategy.Benefiting from the pinning effect and local chemical-and electronic-structure regulations of Mo solute atoms,an ultra-low overpotential(17.3 mV)and an exceptional stability(>100 h)at the typical current density of 10 mA·cm^(−2)are achieved on the ultrasmall Ru-Mo solid-solution nanocrystal catalyst in 1.0 M KOH electrolyte.Density function theory(DFT)calculations gain an insight into the synergistic effect of neighboring Ru and Mo sites in alkaline HER process,where Mo solute atoms are beneficial for the adsorption and activation of water molecules for proton generation and accumulation due to their rich outermost 4d vacant orbitals,while the energy-favorable Ru sites are responsible for the fast deprotonation kinetics of hydrogen intermediates.Our work may provide an interesting route for the development of efficient and stable solid-solution alloy nanocrystals towards alkaline water electrolysis and beyond.
基金Financial support from CNPq, FINEP, PETROBRAS and FAPERJ.
文摘The effect of addition of Ru and Pd to Mo/HZSM-5 catalysts used in the dehydroaromatization of methane was investigated. Catalytic tests and temperature-programmed oxidation results showed that Pd-based catalysts were more selective to naphthalene and suffered strong deactivation. The presence of Ru improved the activity and stability, with a decrease in the carbonaceous deposit probably because of a mechanism of protection of the Mo2C surface.
