From design to efficiency: cobalt-based MOFs for efficient and stable electrocatalysis in hydrogen and oxygen...

The pursuit of clean and renewable energy sources demands efficient technologies for hydrogen production, with water splitting emerging as a promising route. This study explores the use of Cobalt-based Metal-Organic Frameworks (Co-MOFs) as electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Two distinct Co-MOFs, synthesized with the organic linkers 5-nitroisophthalic acid (X1) and pyridine-2,6-dicarboxylic acid (X2), were designed and evaluated for their electrocatalytic performance. X1 exhibited suboptimal morphology and a low specific surface area, resulting in lower catalytical activity and restricting its suitability for long-term applications. In contrast, X2 exhibited exceptional catalytic efficiency with remarkably low overpotentials for both HER (151.7 mV) and OER (180 mV), alongside superior long-term stability. The enhanced electrocatalytic performance of X2 is attributed to its optimized morphology, superior metal-active site distribution, and robust structural integrity, making it an ideal candidate for large-scale water splitting. This work paves the way for the development of high-performance MOF-based electrocatalysts, offering insights for advancing hydrogen generation technologies.