High catalytic performance of core-shell structure ZnCo2O4@NiFe LDH for oxygen evolution reaction

Abstract

It is of great significance to develop efficient and cheap electrocatalysts for oxygen evolution reaction (OER) to promote the further development of water splitting. An effective method is to prepare ideal catalysts by integrating different components, which can increase the number of active sites and generate the synergistic effect among different components. Based on this idea, the NiFe LDH (NiFe Layered Double Hydroxide) nanosheets are anchored on ZnCo2O4 nanowires to form a core-shell structure ZnCo2O4@NiFe LDH. Thanks to the synergistic effect between ZnCo2O4 and NiFe LDH, the ZnCo2O4@NiFe LDH shows excellent catalytic performance for OER. It only needs a low overpotential of 249 mV to achieve the current density of 10 mA cm−2 with a low Tafel slope of 96.7 mV dec-1. Furthermore, after 20 h of stability test, the catalytic performance of the ZnCo2O4@NiFe LDH shows no obvious attenuation. Therefore, this work provides a promising strategy for the future development of OER systems.