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[Display omitted] Developing cost-effective and stable non-noble electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is now the critical issue for large-scale application of zinc-air batteries. Here, we presented a simple method to synthesize highly dispersed cobalt manganate spinel nanodots in-situ embedded in amine-functionalized carbon black. Silane coupling agent 3-aminopropyltriethoxysilane (APTES) played dual roles in the preparation: (1) to achieve amine-functionalization of carbon support; (2) as weak alkali to precipitate metal hydroxides which were then converted to spinel nanodots after mild calcination. The hydrophilicity of the carbon substrate was enhanced by amine modification from APTES to disperse metal oxide evenly, and the electrochemical activity was promoted through the strong interface interaction between embedded spinel nanodots and carbon substrate during the calcination process. As expected, the CoMn 2 O 4 /C-NH 2 -300 catalyst exhibited satisfactory bifunctional catalytic performance for both ORR and OER with an ΔE (E 1/2 -E j10) = 0.75 V, which was lower than most state-of-the-art catalysts. In addition, CoMn 2 O 4 /C-NH 2 -300 as a cathode also exhibited remarkable zinc-air battery performance in alkaline solution. This strategy of APTES as a bifunctional coupling agent provided a novel way to design and explore highly active, durable, and cost-effective catalysts for renewable energy conversion and storage. [ABSTRACT FROM AUTHOR]

Efficient catalysts for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) are of paramount importance for electrochemical energy applications. Herein, a high-efficient carbon-based trifunctional electrocatalyst FeCoP/C is synthesized through a simple one-step supramolecular-assisted method, in which a supramolecular gel structure is formed by phosphoric acid and melamine to allow the efficient and homogeneous incorporation of highly active species. Experimentally, the as-obtained catalysts exhibit practical trifunctional activities in the ORR, OER, and HER. In alkaline electrolytes, requiring overpotentials of 95 and 282 mV to deliver a current density of 10 mA cm−2 for HER and OER, respectively, and presents the significantly increased alkalic ORR activity, with the half-wave potential of 0.849 V. Furthermore, the FeCoP/C also showed good integrated capabilities for Zn-air batteries. This supramolecular-assisted strategy could bring new inspiration to boost the electrocatalytic performance of transition metal-based electrocatalysts for energy conversion applications. [Display omitted] [ABSTRACT FROM AUTHOR]