TRANSITION METAL DISULPHIDE (Co, Ni, Fe) AS ELECTROCATALYST FOR OVERALL WATER SPLITTING

Increasing energy demands and environmental awareness have promoted extensive research on the development of alternative energy conversion and storage technologies that are both highly efficient and environmentally friendly. Among them, water splitting is very appealing, and it is considered as a good renewable and sustainable approach for the generation of green H2 energy, however its implementation at industrial level is hindered due to the requirement of highly active and durable electrode material. Therefore, developing efficient electrocatalysts is of significant importance for high-performance water splitting. In the past few years, much effort has been devoted to the development of alternative electrocatalysts based on transition-metal elements that are low-cost, highly efficient, and have excellent stability. Herein, we developed Fe, Co, and Ni disulfides using microwave synthesis approach. The prepared materials were characterized by using analytical and spectroscopic techniques. Moreover, the prepared materials were evaluated for the electrochemical performance towards oxygen and hydrogen evolution reactions (OER and HER). Furthermore, catalytic activity for urea oxidation reaction (UOR) is also done for the rational treatment of urea. Among the synthesized catalysts, NiS2 exhibited superior bifunctional activity with the lowest overpotentials for both OER (260 mV) and UOR (1.38 V), along with excellent stability and conductivity. CoS2 demonstrated the best HER performance with an overpotential of 240 mV, while FeS2 showed limited electrocatalytic activity due to its poor conductivity and low active site exposure. These findings highlight the effectiveness of microwave-assisted synthesis for fabricating efficient and stable metal disulfide catalysts for water and urea electrolysis.