The global shift towards renewable and low-pollution energy sources has brought hydrogen into the spotlight due to its high energy density, net-zero CO₂ emissions, and efficiency. Electrochemical water splitting (EWS) stands out as a clean energy technology for hydrogen production, powered by renewable sources like solar and wind energy. However, challenges like slow reaction kinetics and costly noble metal catalysts hinder its widespread application. Researchers are focusing on affordable transition metal-based catalysts to improve the efficiency of the oxygen evolution reaction (OER). The urea oxidation reaction (UOR) has shown promise in green hydrogen production with low energy consumption and pollution mitigation. Transition metal-based electrocatalysts, such as 3D hollow sphere structures, are being developed to enhance catalytic performance by providing more active sites and efficient gas bubble release. Overall, advancements in electrochemical water splitting aim to make hydrogen a sustainable and efficient alternative to traditional fossil fuels.