摘要
The rational design of metal-organic frameworks(MOFs)provides potential opportunities for improving energy conversion efficiency.However,developing efficient MOF-based electrocatalysts remains highly challenging.Herein,a strategy involving strain engineering is developed to promote the electrocatalytic performance of MOFs by optimizing electronic configuration and improving the active site.As expected,the optimized CoFe–BDC–NO_(2)exhibits a low overpotential of 292 mV at 10 mA cm^(–2)and a small Tafel slope of 31.6 mV dec^(–1)as oxygen evolution reaction(OER)electrocatalyst.Notably,when CoFe–BDC–NO_(2)is prepared on Nickel foam(NF),the overpotential is only 345 mV at 1 A cm^(–2),which ensures efficient water oxidation properties.Integrating CoFe–BDC–NO_(2)/NF anode in membrane electrode assembly(MEA)for overall water splitting and CO_(2)reduction reaction(CO_(2)RR)tests,the results show that the cell voltages of CoFe–BDC–NO_(2)/NF are 3.14 and 3.09 V at 300 mA cm^(–2)(25℃),respectively,indicating that MOFs have various practical application prospects.The research of the structure-performance relationship reveals the lattice oxygen oxidation mechanism(LOM)where the Co-O-Fe bond is formed during the OER process by changing the electronic environment and coordination structure of CoFe–BDC–NO_(2),and with high valence Co as active center,which provides a deep understanding of the structure design of MOFs and their structural transformation during OER.
基金
financial support from the National Natural Science Foundation of China(Nos.21975175,21878202,22308246)
the Fundamental Research Program of Shanxi Province(No.202203021212266).
