Ni0.85Se Nanosheet Arrays on Nickel Foam as a Robust Non-Noble Metal Electrocatalyst for Energy-Efficient Urea Oxidation

We report the facile synthesis of Ni0.85Se nanosheet arrays directly grown on nickel foam (NF) via a two-step hydrothermal strategy using Ni(OH)2 as a precursor. The two-dimensional architecture offers abundant electroactive sites and efficient charge transport pathways, resulting in remarkable electrocatalytic activity toward the urea oxidation reaction (UOR). The optimized Ni0.85Se/NF electrode delivers a current density of 10 mA cm−2 at a potential of 1.352 V vs. RHE and exhibits a small Tafel slope of 42.3 mV dec−1. Furthermore, it demonstrates excellent durability, maintaining stable operation for over 120 h in alkaline urea-containing electrolyte. These findings highlight Ni0.85Se nanosheets as a cost-effective and durable non-noble-metal electrocatalyst with significant potential for urea oxidation application.