Atomically thick Ni(OH)2 nanomeshes for urea electrooxidation

Abstract

Atomically thick ultrathin nanomeshes (NMs) possessing the inherent advantages of both two-dimensional nanomaterials and porous nanomaterials are attracting increasing interest in catalysis and electrocatalysis. Herein, we report a direct chemical synthesis of atomically thick Ni(OH)₂-NMs by a NaBH₄ assisted cyanogel hydrolysis method, which overcomes the shortcoming of the post-etching method for NM synthesis. Various physical characterization methods show that the as-synthesized Ni(OH)₂-NMs have 1.7 nm thickness, a big surface area, abundant nanoholes, and numerous surface/edge atoms with low-coordination numbers. The as-synthesized Ni(OH)₂-NMs show a better electrocatalytic performance for the urea oxidation reaction than conventional Ni(OH)₂ nanoparticles without holes in the alkaline electrolyte, including a lower onset oxidation potential, faster reaction kinetics, and higher mass activity.