Interfacial construction and lattice distortion-triggered bifunctionality of Mn-NiS/Mn-Ni3S4 for H2 production

The hydrogen is described as a clean and sustainable alternative to fossil fuels in numerous energy systems. Hydrolysis is an important method for high purity, high volume hydrogen production. In order to accelerate the kinetics of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media, it is essential to explore efficient catalysts. In this paper, the nanoscale self-supported Mn-NiS/Mn-Ni3S4 composite catalysts was assembled on nickel foam. Benefiting from the lattice distortion and vacancy defects caused by the doping of Mn elements, the catalysts exposed an increasing number of electrochemical surfaces and effective active sites, showing impressive electrochemical performance with a HER overpotential of only 94.2 mV at 10 mA/cm2 and an OER overpotential of only 253 mV to drive 50 mA/cm(2). Applying as the bifunctional catalysts, the Mn-NiS/Mn-Ni3S4 couple only achieved a low voltage of only 1.52 V to drive 10 mA/cm2. This paper pro-vides new ideas and references for the rational design of high-performance sulfide catalysts with non-precious metal composites.

Automated summary

In this paper, nanoscale self-supported Mn-NiS/Mn-Ni3S4 composite catalysts were assembled on nickel foam to accelerate the kinetics of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media. The catalysts showed impressive electrochemical performance with low overpotentials, making them potential candidates for high purity, high volume hydrogen production and electrolysis reactions.