Fabrication of the novel NiFe-LDHs @γ-MnOOH nanorod electrocatalyst for effective water oxidation

Abstract

The development of highly efficient electrocatalysts for water splitting is great critical for the massive production of hydrogen energy. In this work, a kind of novel NiFe-LDHs@γ-MnOOH nanorod electrocatalyst was fabricated via the two-step method. Firstly, γ-MnOOH nanorods were grown in situ on the nickel foam conductive substrate by a simple hydrothermal method. Then, NiFe-LDHs were combined on the γ-MnOOH/NF surface by electrochemical deposition to prepare the NiFe-LDHs@γ-MnOOH/NF core-shell structure catalyst. Due to good charge transfer capability, high exposure of active sites as well as the interfacial interaction between NiFe-LDHs and γ-MnOOH, the obtained core-shell structure catalyst exhibited excellent oxygen evolution reaction (OER) activity in alkaline media. The overpotential of 226 mV at the current density of 10 mA cm−2 for OER could be achieved with a low Tafel slope of 88 mV dec- 1, and almost no current density loss occurred after the 24 h i-t stability testing. Furthermore, this catalyst also possessed good performance in overall water splitting, which could afford a current density of 10 mA cm−2 by 1.69 V cell voltage.