Controlling the microenvironment by introducing dual metal atoms into ZIF-L to enhance hydrogen evolution activity

Abstract

In this study, we introduce an efficient strategy to enhance the electrocatalytic performance of ZIF-L by injecting dual metal atoms, specifically Co and Cu, using a facile hydrothermal reaction method. The optimized Co,Cu-ZIF-L composites showed exceptional hydrogen evolution activities with overpotentials of 70 and 145 mV under 10 and 50 mA cm⁻² in alkaline media. The Co,Cu-ZIF-L composites also displayed excellent cycling stability (∼ 90 h) for hydrogen evolution. The enhanced electrocatalytic performance is attributed to the dual metal atoms, which not only introduce abundant active sites but also improve the structural integrity and catalytic kinetics by regulating the catalytic microenvironment. Density functional theory calculations further support that the injection of Co and Cu atoms into the ZIF-L optimizes the free adsorption energy of hydrogen intermediates, accelerating HER kinetics. This work confirms that injecting highly conductive metal atom into MOFs to regulate the catalytic microenvironment is a potential route to significantly increase the electrocatalytic activity of MOFs.