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arXiv · 2305.00764

Molybdenum diselenide-manganese porphyrin bifunctional electrocatalyst for hydrogen evolution reaction and selective hydrogen peroxide production

Abstract

Electrochemical reactions for hydrogen and hydrogen peroxide production are essential for energy conversion to diminish energy crisis, but still lack efficient electrocatalysts. Development of non\-noble metal bifunctional electrocatalysts for hydrogen evolution and 2e oxygen reduction reaction to ease reaction kinetics is a challenging task. Integration of single components by employing easy strategies provides a key\-step towards the realization of highly active electrocatalysts. In this vein, MoSe2 owns catalytic active sites and high specific surface area but suffers from insufficient conductivity and high catalytic performance that noble\-metals provide. Herein, MoSe2 was used as a platform for the incorporation of manganese metallated porphyrin. The developed hybrid, namely MoSe2\-MnP, by the initial metal\-ligand coordination and the subsequent grafting with MnP was fully characterized and electrochemically assessed. The bifunctional electrocatalyst lowered the overpotential toward hydrogen evolution, improved reaction kinetics and charge transfer processes and was extremely stable after 10000 ongoing cycles. Simultaneously, rotating ring disk electrode analysis showed that oxygen reduction proceeds through the 2e pathway for the selective production of hydrogen peroxide with a high yield of 97 percent. The new facile modification route can be applied in diverse transition metal dichalcogenides and will help the development of new advanced functional materials.

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Antonia Kagkoura, Christina Stangel, Raul Arenal, Nikos Tagmatarchis. 2023-05-01. Molybdenum diselenide-manganese porphyrin bifunctional electrocatalyst for hydrogen evolution reaction and selective hydrogen peroxide production. https://doi.org/10.1021/acs.jpcc.2c04723

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