3D nickel diselenide architecture on nitrogen-doped carbon as a highly efficient electrode for the electrooxidation of methanol and urea

Highlights: • 3D nickel diselenide architectures on nitrogen-doped carbon. • The influence of selenization temperature on the oxidation performance of methanol and urea. • NiSe₂/NC-450 exhibits high activity and durability for methanol oxidation and urea oxidation. -- Abstract: The development of an electrocatalyst for the efficient catalysis of methanol or urea is essential for solving energy and environmental problems. This study successfully synthesizes nickel selenide and 3D nickel diselenide architectures on N-doped carbon using a NaCl-assisted method and selenization temperature regulation. The 3D architecture of the nickel diselenide with N-doped carbon obtained by selenization at 450 °C (NiSe₂/NC-450) is a useful electrocatalyst for the methanol oxidation reaction (MOR) and urea oxidation reaction (UOR). This NiSe₂/NC-450 electrode displays good catalytic activity for MOR (high peak current density of ~164.68 mA cm⁻², low oxidation potential of ~1.33 V at 10 mA cm⁻²) and UOR (high peak current density of ~136.04 mA cm⁻², low oxidation potential of ~1.32 V at 10 mA cm⁻²). The strong methanol and urea reaction performance of NiSe₂/NC-450 is attributed to the expanded electrochemically active area after selenization and the enhanced conductivity after N-doped carbon. This study provides a new way to prepare and utilize inexpensive transition metal-based materials as efficient and stable anodic oxidation electrocatalysts.