Hollow Co9S8@NiFe-LDH nanoarrays supported by nickel foam for boosting the overall water-splitting performance

Rational design of efficient, low-cost, and durable electrocatalyst for water-splitting is of great importance in the utilization of renewable energy. In this work, we report a facile heterostructure of nickel foam supporting hollow Co9S8 nanoarrays wrapped by NiFe-layered double-hydroxide (Co9S8@NiFe-LDH/NF) as the electrocatalyst for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) to improve the water-splitting efficiency. By the structural design, the strong electronic interaction among each component could offer more actives sites, higher charge transfer capability and better durability. As a result, excellent electrocatalytic activity for HER and OER are obtained. In 1 M KOH solution, the Co9S8@NiFe-LDH/NF exhibits low overpotentials of 287 mV for OER and 280 mV for HER to achieve catalytic current density of 50 mA cm(-2). This work offers a new avenue to construct efficient and low-cost electrocatalyst for water-splitting.