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arXiv · 2403.17744

Facile synthesis of micro-flower NiCo2O4 assembled by nanosheets efficient for electrocatalysis of water

Yujie Wang·Yan Duan·Yuwen Chen·Man Zhang·Yuchen Wang·Bin Liu·Xiaodie Zhang·Yutong Zhang·Kai Yan
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Abstract

Effective regulation of the morphology of transition metal spinel structures is crucial for creating efficient and stable bifunctional catalysts for electrocatalysis of water. In this work, micro-flower NiCo2O4 (F-NCO) assembled by nanosheets via a chemical template method for the simultaneous promotion of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Electronic microscope analysis revealed that the thickness of the F-NCO catalyst was only 2.7% of that of the NiCo2O4 bulk (B-NCO), and this ultrathin lamellar structure was conducive to further exposure of the active site and improved reaction kinetics. The F-NCO catalyst exhibited superior HER and OER performance (10 = 236 and 310 mV) and robust long-term stability over the B-NCO catalyst in 1.0 M KOH, with a 2.68-fold and 4.16-fold increase in active surface area and a 0.42-fold and 0.61-fold decrease in charge transfer resistance values, respectively. This micro-flower-structured electrode has remarkable electrocatalytic property and long-term durability, providing a novel insight for characterizing cost-effective and high-performance bifunctional electrocatalysts.

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Yujie Wang, Yan Duan, Yuwen Chen, Man Zhang, Yuchen Wang, Bin Liu, Xiaodie Zhang, Yutong Zhang, Kai Yan. 2024-03-25. Facile synthesis of micro-flower NiCo2O4 assembled by nanosheets efficient for electrocatalysis of water. https://arxiv.org/abs/2403.17744

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