Enhanced electrocatalytic performance of carbon-coated NiCoO2/NiCo composites for efficient water splitting

Abstract

Abstract The urgent need for sustainable energy conversion technologies has propelled the development of efficient and cost-effective electrocatalysts for water splitting. In this study, we synthesize carbon-coated NiCoO2/NiCo@C composites through the calcination of CoNi Prussian Blue Analogues nanocubes, aiming to enhance the electrocatalytic performance for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Our findings demonstrate that the NiCoO2/NiCo@C composites exhibit outstanding catalytic activity, achieving low overpotentials of 329 mV for OER and 61.9 mV for HER at a current density of 10 mA cm−2, with robust stability under prolonged operational conditions. The enhanced activity is attributed to the large interface area and high density of exposed active sites facilitated by the unique heterojunction structure of NiCoO2/NiCo particles embedded in carbon frameworks and nanotubes. This architecture not only prevents the agglomeration of metal nanoparticles but also promotes efficient electron and proton transfer, significantly boosting electrochemical performance. This study introduces a promising approach for designing high-performance, cost-effective electrocatalysts, paving the way for their application in industrial water electrolysis.

Keywords

• CoNi PBA
• Water splitting
• Carbon coated
• Annealing experiment