ScholarWorks@중앙대학교

초록

The advancement of sustainable energy technologies critically depends on the development of efficient electrocatalysts for the oxygen evolution reaction (OER). In this study, we introduce a novel NiFeCo-phytic acid (PA)@Mo2CTx hybrid catalyst, synthesized by etching zeolitic imidazolate framework-67 with PA, yielding NiFeCo-PA that completely transforms into NiFeCoOOH during the OER. This transformation, driven by the removal of PA and the incorporation of hydroxide ions, enhances the electronic structure and increases the availability of active sites. The interaction with the Mo2CTx MXene is further optimized to be highly favorable, as the morphology of NiFeCoOOH changes from hollow nanoboxes to nanosheets during the OER, optimizing charge transfer and further improving catalytic activity. The NiFeCo-PA@Mo2CTx hybrid catalyst delivers an overpotential as low as 220 mV at 10 mA cm−2, a Tafel slope of 62.05 mV dec−1, and remarkable stability. Zn–air battery tests revealed that the hybrid catalyst outperforms conventional Pt/C + RuO2 cells, demonstrating improved power densities and good long-term cycling stability. These findings highlight the significant roles of NiFeCoOOH transformation, PA removal, and Mo2CTx interaction in enhancing OER performance, suggesting a promising strategy for designing high-performance catalysts tailored for energy conversion and storage systems.

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