MoS2/NiS core-shell structures for improved electrocatalytic process of hydrogen evolution

It is important to develop a low-cost and easy-prepared electrocatalyst for hydrogen evolution reaction. In this work, MoS2/NiS hierarchical nanostructures (HHs) were fabricated on Ni foam by a simple one-step hydrothermal reaction using Ni foam as raw materials directly. Owing to the unique synthetic strategy that provide uniform MoS2/NiS HHs structure on the porous Ni foam, generate abundant active surfaces, small resistance, furthermore it is beneficial for carrier migration and contributing to a large number of active sites. Excellent electrocatalytic performances are obtained such as an overpotential of only ~84.1 mV to reach the current density of 10 mA cm−2, a Tafel slope of 76.9 mV dec−1 and a small inherent resistance of 6.33 Ω. More importantly, a quick current response under multistep potentials is realized and an excellent stability retained after 3000 cycles of CV test. Besides, a DC power to supply a device (MnMoO4//MoS2/NiS HHs B) under 1.6 V can generate a current density of 21 mA cm−2, demonstrating its practical application.