Shining light on layered metal phosphosulphide catalysts for efficient water electrolysis: preparation, promotion strategies, and perspectives

Electrocatalytic water splitting can efficiently produce clean hydrogen energy, which could alleviate the global energy crisis and reduce environmental pollution. Highly active and earth-abundant electrocatalysts are crucial for the sustainable development of a future hydrogen economy. Layered metal phosphosulphides (MPS₃, M = Fe, Co, Ni, Pd, Mn) are novel two-dimensional (2D) materials that have attracted tremendous interest in the catalytic community. However, the low intrinsic activity of bulk MPS₃ seriously hinders its wide application as an efficient electrocatalyst for the hydrogen/oxygen evolution reaction (HER/OER) and overall water splitting (OWS). For better practical catalytic implementation of MPS₃, a range of performance promotion strategies have been successfully proposed, including few-layer exfoliation, elemental doping, and heterojunction construction, among others. In this review, we have summarized and discussed the design, preparation and promotion strategies of MPS₃-based electrocatalysts for water splitting. In addition, the future perspectives, opportunities, and challenges for MPS₃-based electrocatalysts are also briefly discussed. This review should provide effective guidance for the design and development of advanced electrocatalysts for hydrogen production.