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The oxygen evolution reaction (OER) generally exists in electrochemistry‐enabled applications that are coupled with cathodic reactions like hydrogen evolution, carbon dioxide reduction, ammonia synthesis, and electrocatalytic hydrogenation. The OER heavily impacts the overall energy efficiency of these devices because the sluggish OER kinetics result in a huge overpotential, thus, a large amount of efficient catalysts are needed. The benchmark iridium and ruthenium (Ir/Ru)‐based materials (mostly used in acid media) are, however, significantly limited by their scarcity. Non‐precious metal‐based catalysts (NPMCs) have emerged as the most promising alternatives; however, they tend to degrade quickly under the harsh operating conditions of typical OER devices. Another challenge is the unsatisfying performance of OER catalysts when integrated in real‐world devices. Herein, the OER active sites for three mainstream types of NPMCs including non‐precious transition metal oxides/(oxy)hydroxides, metal‐free carbon materials, and hybrid non‐precious metal and carbon composites are reviewed. In addition, possible degradation mechanisms for active sites and mitigation strategies are discussed in detail. This review also provides insights into the gaps between R&D of NPMCs for the OER and their applications in practical devices. [ABSTRACT FROM AUTHOR]

The performance of Zn-Air battery (ZAB) is often limited by sluggish kinetics of oxygen reduction reaction (ORR) and oxygen evolution reactions (OER). In this work, a flower-like porous carbon is designed for the synthesis of the Co/Zn/Mn@NC. Due to a highly porous structure and abundant active sites, the as-prepared Co/Zn/Mn@NC-800 shows a half-wave potential of 0.86 V for ORR, and an overpotential of 360 mV for OER at 10 mA/cm2, suggesting an excellent bifunctional catalytic activity. The ZAB with Co/Zn/Mn@NC-800 delivers a power density of 163 mW/cm2 and a specific capacity of 832 mA h/g Zn , higher than that with Pt/C + RuO 2 (147 mW/cm2 and 802 mA h/g Zn). Moreover, the Co/Zn/Mn@NC-800-based ZAB has a superior long-term stability with a negligible decline of efficiency (0.3%) after 534 cycles (>150 h). These results suggest that the synthesized Co/Zn/Mn@NC catalyst has a great potential for the practical application in ZABs. [Display omitted] • Flower-like porous carbon for the synthesis of trimetallic Co/Zn/Mn@NC. • The Co/Zn/Mn@NC-800 shows a half-wave potential of 0.86 V for ORR. • The Co/Zn/Mn@NC-800 has an overpotential of 360 mV for OER at 10 mA/cm2. • Zinc-air battery with Co/Zn/Mn@NC-800 has a power density of 163 mW/cm2. • The Co/Zn/Mn@NC-800-based zinc-air battery has a superior long-term stability. [ABSTRACT FROM AUTHOR]