Enhancing Hydrogen Generation by Anodic Oxidation of Urea over Superb Hydrophilic Hierarchical Ni, S co‐Doped Co3(PO4)2 Nanosheets

Abstract Surface wettability are of great significance to electrocatalysts for various electrochemical reaction. In this work, Ni, S co‐doped Co 3 (PO 4 ) 2 nanosheets on Ni foam (Ni‐S‐Co 3 (PO 4 ) 2 NSs) with high hydrophilicity and hierarchical structure are synthesized. The doping of S is the key factor to achieve an ultrahigh hydrophilic surface, identified by the contact angle measurement. As except, the as‐prepared Ni‐S‐Co 3 (PO 4 ) 2 NSs display prominent activity for urea oxidation reaction (UOR), which reach the current density of 10 mA cm −2 at a low potential of 1.28 V (vs. reversible hydrogen electrode, RHE) with excellent stability. Remarkably, when paired with Ni‐Mo electrode to fabricate overall urea electrocatalysis device, a cell potential of mere 1.33 V is required to afford the current density of 10 mA cm −2 , making the Ni‐S‐Co 3 (PO 4 ) 2 NSs an outstanding UOR electrocatalyst for efficient hydrogen production.