Application of Transition Metal Phosphides to Electrocatalysis: An Overview

Recently, sustainable energy alternatives have attracted the scientific community and policymakers as concerns over global warming and depletion of fossil fuels have increased significantly. Substituting H₂ gas as a primary source for our daily energy consumption under the guideline of the hydrogen economy concept has not progressed as anticipated because of inadequate efficiency associated with the generation (electrolyzer) and utilization (fuel cell) devices. A critical challenge is to design strategies for fabricating electrocatalysts derived from earth-rich elements to address cost and performance concerns. In this context, nanostructured transition metal phosphides (TMPs) have emerged as highly efficient electrocatalysts. The excellent electrocatalytic performance of TMPs is ascribed to their suitable charge transfer from metal to phosphorous as well as the easy transfer process of a proton-coupled electron during hydrogen evolution reaction. This overview focuses on the materials fabrication and the associated challenges in the design and development of TMP-based catalysts.