Interface strain engineering of Ir clusters on ultrathin NiO nanosheets for electrochemical water splitting over 1800 hours

Strain engineering of two-dimensional(2D)material interfaces represents a powerful strategy for enhanc-ing the electrocatalytic activity of water splitting.However,maintaining catalytic stability under various harsh conditions by introducing interface strain remains a great challenge.The catalyst developed and evaluated herein comprised Ir clusters dispersed on 2D NiO nanosheets(NSs)derived from metal organic frameworks(lr@NiO/C_(BDc)),which displays a high activity and stability under all pH conditions,and even a change of only 1%in the applied voltage is observed after continuous electrocatalytic operation for over 1800 h under alkaline conditions.Through combined experimental and computational studies,we found that the introduced interfacial strain contributes to the outstanding structural stability of the Ir@NiO/CBDC catalyst,arising from its increased Ir and Ni vacancy formation energies,and hence suppressing its leach-ing.Moreover,strain also enhances the kinetically sluggish electrocatalytic water splitting reaction by op-timizing its electronic structure and coordination environment.This work highlights the effects of strain on catalyst stability and provides new insights for designing widely applicable electrocatalysts.