Facile one-pot synthesis of nanocoral-like cerium-activated cobalt selenide: a highly efficient electrocatalyst for oxygen evolution reaction

The development of hydrogen production via environment-friendly and efficient electrochemical water splitting technology leans heavily on the exploitation of highly active and durable oxygen evolution reaction (OER) electrocatalysts. Herein, nanocoral-like cerium-activated cobalt selenide (Ce-CoSe₂) nanocomposites to enhance the OER catalytic activity have been successfully prepared by one-pot hydrothermal route via simply altering the cerium content. Owing to the ingenious introduction of cerium, as-prepared Ce-CoSe₂ electrode displays remarkable OER performance in comparison with CoSe₂. The nanocoral-like Ce-CoSe₂ catalyst prepared under optimal condition just needs low overpotential of 276 and 398 mV at 10 and 50 mA cm^?2, respectively. Additionally, it attains the current density of 255 mA cm^?2 at the potential of 2.0 V vs. RHE, and shows long-term stability during OER. This work offers a simple and feasible pathway for the design and construct of metal dichalcogenides for green and renewable hydrogen production by electrocatalytic water splitting.

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Self-assembled nanocotton-like Co–B–P/bacterial cellulose based carbon nanofiber as highly efficient electrocatalyst for oxygen evolution reaction

It is urgent and challenging to exploit highly efficient oxygen evolution reaction (OER) catalysts for water splitting. Bacterial cellulose based carbon nanofiber (BCCNF) is highlighted for its 3D network structure, abundant surface functional groups and good conductivity. Herein, based on the different molar ratio of P/B precursor, a series of nanocotton-like Co–B–P/BCCNF electrocatalysts have been designed and prepared via a simple electroless deposition. When the molar ratio of P/B precursor is 3/7, nanocotton-like Co–B–P/BCCNF catalyst exhibits prominent catalytic performances, delivering the current density of 10 and 50 mA cm^?2 at low overpotentials of only 262 and 391 mV, respectively. Besides, it exhibits long-term stability for durative OER in alkaline solution. This result indicates that nanocotton-like Co–B–P/BCCNF catalyst has great potential as OER catalysts for large-scale hydrogen production via water splitting.