Metal-organic framework derived NiMo polyhedron as an efficient hydrogen evolution reaction electrocatalyst.

Abstract Exploring efficient electrocatalyst for H 2 evolution reaction (HER) and replacing the noble metal-based catalysts with inexpensive non-noble metal-based HER catalyst is of great importance for the practicality of hydrogen powered clean technologies. Here, we explore a new class of metal organic framework (MOF) composite (NiMo polyhedron) as an active electrocatalyst material for HER application - synthesized through the conventional hydrothermal process. The bimetallic MOF system having grown on Nickel foam (NiMo/NiMoO 4 @NC/NF) delivers higher catalytic activity by achieving a current density of 10 mA cm−2 at a low overpotential of 80 mV, with a Tafel slope of 98.9 mV dec−1 (0.5 M H 2 SO 4), comparing favorably with the electrochemical enactment of existing bimetallic MOF-based catalysts. The enhanced HER activity of the synthesized MOF, is primarily due to the structural merits of MOF and the synergy between the MOF and the guest species (Ni and Mo metal atoms). Adding to the excellent HER performance, the electrode also exhibits good stability in acidic medium for a prolonged duration of 24 h. Hence, the synthesized low-cost, non-Pt electrode MOFs with its greater HER performance can be an auspicious applicant as an HER catalyst for water splitting and hydrogen generation applications. Graphical abstract Unlabelled Image Highlights • Noble, Pt free alternate electrocatalysts for HER were identified. • Ni, Mo based bimetallic MOFs were prepared by hydrothermal process. • The synthesized NiMO-MOFs possessed polyhedron morphology. • It achieved a current density of 10 mA cm−2 at a low overpotential of 98.9 mV. [ABSTRACT FROM AUTHOR]