A novel bimetallic organic framework catalyst induced by dual-ligand for highly efficient oxygen evolution

Abstract

With the continuous advancement of non-noble electrocatalysts, metal-organic frameworks (MOFs) are emerging as a promising substitute for noble metal nanomaterials in oxygen evolution reaction (OER) due to their larger pre-development and higher cost-effectiveness. However, there are still challenges in modifying the electronic structure of MOFs at the molecular level to enhance their activity of OER. Herein, bimetallic CoNi MOFs were utilized and modified with terephthalic acid (A) and 2, 5-dihydroxyterephthalic acid (B) (A2.5B-CoNi MOFs) through a straightforward hydrothermal method. By adjusting the ratio of A and B dual-ligand, the A2.5B-CoNi MOFs with the best ligand ratio exhibit significantly enhanced OER activity with an overpotential of only 300 mV at a current density of 10 mA cm−2, a low Tafel slope of 45.27 mV dec−1. In addition, A2.5B-CoNi MOFs also have better long-term stability than commercial RuO2. This study provides a research direction for the development of high-performance OER electrocatalysts based on dual-ligand MOFs.