Nickel-based MOF derived Ni @ NiO/N-C nanowires with core-shell structure for oxygen evolution reaction

Nickel-based metal organic framework materials were first prepared by hydrothermal method and used as the precursor. Ni/nitrogen-carbon (Ni-N-C), Ni@NiO-N-C and NiO-N-C mixtures derived from metal organic skeleton were successfully prepared by controlling the heat treatment conditions and applied in the electrocatalytic oxygen evolution reaction (OER). Through a series of research of OER catalytic performance, OER process kinetics, and stability, the as-prepared Ni @ NiO/N-C nanowires (NW) (250 degrees C) with core-shell structure showed the most prominent activity. Compared with other derived mixed materials, the oxygen evolution overpotential was 390 mV at the current density of 10 mA cm(-2), and the Tafel slope was 100 mV dec(-1). Moreover, the material showed excellent stability without significant decrease of activity after a long time of testing. The detail study regarding the formation and evolution of Ni/NiO NWs is of considerable value and may offer prospects for developing highly active electrocatalysts in electrochemical energy devices. (C) 2019 Elsevier Ltd. All rights reserved.