MOF derived NiCo-LDH hollow structure for oxygen evolution reaction.

Transition metal based materials with hollow structure are considered as advanced electrocatalysts for oxygen evolution reaction (OER). This study reports the NiCo-LDH nanosheets assembled hollow structure arrays on nickel foam, which are synthesized by solvothermal method with ZnCo-MOF nanopolyhedra as precursors. Taking advantage of the nanosheets constructed hollow structure, the obtained sample exhibits good OER catalysis activity with low overpotential of 303 mV at current density of 100 mA cm−2 and satisfied stability. It is demonstrated that Ni2+ and Co2+ are oxidized into Ni3+ and Co3+, which play as robust catalysis sites and greatly promote the catalysis performance for OER. This work demonstrates a promising strategy for controllable preparation of hollow structures of transition metal materials for electrochemical water splitting. NiCo-LDH nanosheets assembled hollow architecture arrays on nickel foam are prepared for advanced OER application due to the structural advantages and the robust active sites of oxidized Ni and Co elements. [Display omitted] • NiCo-LDH nanosheets assembled hollow structure arrays are synthesized. • Structural advantages improve surface area and active sites for OER. • Ni and Co are oxidized to high chemical states to promote OER. • Low overpotential of 303 mV at 100 mA cm−2 is obtained for OER. [ABSTRACT FROM AUTHOR]