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[Display omitted] • Pore size-controlled Fe-doped Co 3 O 4 have been prepared using silica beads of different sizes. • FCO-T-500 synthesized using 500 nm-sized silica beads exhibited the best OER performance. • The improved performance of FCO-T-500 can be attributed to the optimal pore size. • The improved performance of FCO-T-500 can result from sufficient surface OH and H 2 O groups. Low-cost and highly efficient anode catalysts are required for the oxygen evolution reaction (OER), which is integral to the commercialization of alkaline-based water electrolysis. Herein, pore size-controlled Fe-doped Co 3 O 4 nanostructures are prepared as non-precious metal anode catalysts using a hard-template method with silica beads of different sizes, ranging from 20 to 1000 nm in diameter. The pore size distribution and specific surface area of the catalysts are measured by nitrogen adsorption/desorption analysis and mercury intrusion porosimetry. The electrochemical properties and OER performances of the catalysts are evaluated in half and unit cells, respectively. Among the catalysts studied, FCO-T-500 synthesized using 500 nm-sized silica beads exhibits the best OER activity and stability, given by a high current density of 847 mA cm−2 at 1.8 V and superior 100 h-stability during single cell test of anion exchange membrane water electrolysis. The improved OER performance of FCO-T-500 can be attributed to the optimal pore size favorable for gas diffusion and mass transport, sufficient surface OH and H 2 O groups produced via KOH leaching, the largest number of electrocatalytic active sites, and the fastest charge-transfer reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] Lithium-oxygen batteries (LOBs) are next-generation electrochemical power sources with significantly high capacities and energy densities. In particular, Li 2 O 2 produced during charging exhibits a low electrical conductivity and insolubility, which leads to low energy efficiency in LOBs. Thus, various catalysts are studied to solve essential problems such as the sluggish decomposition rate of Li 2 O 2. In this study, a redox polymeric catalyst (RPC-FePc) is fabricated on an air electrode by combining iron(Ⅱ) phthalocyanine (FePc) as the redox mediator and polyvinylidene fluoride as the binder. The RPC-FePc applied to liquid electrolyte- and gel polymer electrolyte-based LOBs exhibit improved electrochemical properties, that is, increased cycling efficiencies and a reduced IR drop, compared to an RPC-free LOB. [ABSTRACT FROM AUTHOR]