A General Sol‐Gel Route to Fabricate Large‐Area Highly‐Ordered Metal Oxide Arrays Toward High‐Performance Zinc‐Air Batteries

Abstract A universal method is demonstrated for the fabrication of large‐area highly ordered microporous arrayed metal oxides based on a high‐quality self‐assembly opal template combined with a sucrose‐assisted sol‐gel technique. Sucrose as a chelating agent optimizes precursor infiltration and regulates both oxide formation and the melting process of polystyrene templates, thus preventing crack formation during infiltration and calcination. As a result, over 20 metal element‐based 3DOM oxides with arbitrary compositions are successfully prepared. Therein, a champion electrocatalyst RuCoO x ‐IO exhibits outstanding bifunctional oxygen activity with an ultra‐narrow oxygen potential gap of 0.598 V, and the Zn‐air batteries based on RuCoO x ‐IO air cathode operates for 1380 h under fast‐charging cycling (50 mA cm −2 ), and reaches a high energy efficiency of 69.5% in discharge‐charge cycling. In situ spectroscopy characterizations and density functional theory reveal that the rational construction of Ru─O─Co heterointerface with decoupled multi‐active sites and mutual coupling of RuO 2 and Co 3 O 4 facilitate interfacial electron transfer, leading to an optimized d ‐band centers of active Ru/Co and a weakened spin interaction between oxygen intermediates and Co sites, so as to enhance the adsorption ability of * OOH on interfacial Co sites for fast ORR kinetics while favoring the desorption of oxygen intermediates on interfacial Ru during OER.