Intralayered Ostwald Ripening to Ultrathin Nanomesh Catalyst with Robust Oxygen‐Evolving Performance

An etching‐intralayered Ostwald ripening process is proposed, which leads to the formation of a β‐Ni(OH)2 ultrathin nanomesh with abundant and uniformly distributed nanopores of 3–4 nm. The nanomesh catalyst exhibits outstanding oxygen evolution reaction performance, with high catalytic current density and superior long‐term stability, making this Earth‐abundant nanomesh catalyst a promising candidate for commercial water splitting.