Delicately designed metal–organic framework(MOF)-derived nanostructured electrocatalysts are essential for improving the reaction kinetics of the oxygen evolution reaction and tuning the selectivity of small organic ...Delicately designed metal–organic framework(MOF)-derived nanostructured electrocatalysts are essential for improving the reaction kinetics of the oxygen evolution reaction and tuning the selectivity of small organic molecule oxidation reactions.Herein,novel oxalate-modified hollow CoFe-based layered double hydroxide nanocages(h-CoFe-LDH NCs)and yolk–shell ZIF@CoFe-LDH nanocages(ys-ZIF@CoFe-LDH NCs)are developed through an etching–doping reconstruction strategy from a Co-based MOF precursor(ZIF-67).The distinctive nanostructures,along with the incorporation of the secondary metal element and intercalated oxalate groups,enable h-CoFe-LDH NCs and ys-ZIF@CoFe-LDH NCs to expose more active sites with high intrinsic activity.The resultant h-CoFe-LDH NCs exhibit outstanding OER activity with an overpotential of only 278 mV to deliver a current density of 50 mA cm^(-2).Additionally,controlling the reconstruction degree enables the formation of ys-ZIF@CoFe-LDH NCs with a yolk–shell nanocage nanostructure,which show outstanding electrocatalytic performance for the selective ethylene glycol oxidation reaction(EGOR)toward formate,with a Faradaic efficiency of up to 91%.Consequently,a hybrid water electrolysis system integrating the EGOR and the hydrogen evolution reaction using Pt/C||ys-ZIF@CoFe-LDH NCs is explored for energy-saving hydrogen production,requiring a cell voltage 127 mV lower than water electrolysis to achieve a current density of 50 mA cm^(-2).This work demonstrates a feasible way to design advanced MOF-derived electrocatalysts toward enhanced electrocatalytic reactions.展开更多
基金financial support of the National Natural Science Foundation of China(21901246,22105203 and 22205235)the Natural Science Foundation of Fujian Province(2020J01116 and 2021J06033)+1 种基金support under the Australian Research Council's Discovery Projects funding scheme(DP220103458)Future Fellowship(FT190100658).
文摘Delicately designed metal–organic framework(MOF)-derived nanostructured electrocatalysts are essential for improving the reaction kinetics of the oxygen evolution reaction and tuning the selectivity of small organic molecule oxidation reactions.Herein,novel oxalate-modified hollow CoFe-based layered double hydroxide nanocages(h-CoFe-LDH NCs)and yolk–shell ZIF@CoFe-LDH nanocages(ys-ZIF@CoFe-LDH NCs)are developed through an etching–doping reconstruction strategy from a Co-based MOF precursor(ZIF-67).The distinctive nanostructures,along with the incorporation of the secondary metal element and intercalated oxalate groups,enable h-CoFe-LDH NCs and ys-ZIF@CoFe-LDH NCs to expose more active sites with high intrinsic activity.The resultant h-CoFe-LDH NCs exhibit outstanding OER activity with an overpotential of only 278 mV to deliver a current density of 50 mA cm^(-2).Additionally,controlling the reconstruction degree enables the formation of ys-ZIF@CoFe-LDH NCs with a yolk–shell nanocage nanostructure,which show outstanding electrocatalytic performance for the selective ethylene glycol oxidation reaction(EGOR)toward formate,with a Faradaic efficiency of up to 91%.Consequently,a hybrid water electrolysis system integrating the EGOR and the hydrogen evolution reaction using Pt/C||ys-ZIF@CoFe-LDH NCs is explored for energy-saving hydrogen production,requiring a cell voltage 127 mV lower than water electrolysis to achieve a current density of 50 mA cm^(-2).This work demonstrates a feasible way to design advanced MOF-derived electrocatalysts toward enhanced electrocatalytic reactions.