A Cost-Efficient Bifunctional Ultrathin Nanosheets Array for Electrochemical Overall Water Splitting.

The design of cost-efficient earth-abundant catalysts with superior performance for the electrochemical water splitting is highly desirable. Herein, a general strategy for fabricating superior bifunctional water splitting electrodes is reported, where cost-efficient earth-abundant ultrathin Ni-based nanosheets arrays are directly grown on nickel foam (NF). The newly created Ni-based nanosheets@NF exhibit unique features of ultrathin building block, 3D hierarchical structure, and alloy effect with the optimized Ni Fe layered double hydroxide@NF (Ni Fe LDH@NF) exhibiting low overpotentials of 210 and 133 mV toward both oxygen evolution reaction and hydrogen evolution reaction at 10 mA cm in alkaline condition, respectively. More significantly, when applying as the bifunctional overall water splitting electrocatalyst, the Ni Fe LDH@NF shows an appealing potential of 1.59 V at 10 mA cm and also superior durability at the very high current density of 50 mA cm .