Tailoring d-band centers in NiCo2O4 through phase engineering for high-performance ethanol oxidation and coupled hydrogen generation

作者：Fozia Sultana, Meijie Shi, Renkun Li, Renkun Li, Jie Zhang, Xiaoqing Yan, Tong Wei, Renhong Li, Renhong Li, Renhong Li · 发表于：Applied Catalysis B: Environmental · 年份：2025 · DOI：10.1016/j.apcatb.2025.126346 · 被引用次数：2 · 研究领域：Electrocatalysts for Energy Conversion、Supercapacitor Materials and Fabrication、Catalysis for Biomass Conversion

Amorphous/crystalline heterostructures have emerged as an effective strategy for optimizing electrocatalytic performance by leveraging the complementary properties of both structural phases. In this study, a nickel cobalt spinel catalyst featuring an amorphous/crystalline heterophase (A/C-NiCo 2 O 4 /NF) was synthesized on nickel foam via a combination of hydrothermal treatment and electrochemical transformation. This heterostructured catalyst demonstrates significantly enhanced activity toward the ethanol oxidation reaction (EOR), achieving a high current density of 400 mA cm⁻ 2 at a low potential of 1.36 V. The nanoarray architecture, composed of interconnected hexagonal nanosheets, provides a high electrochemically active surface area, ensuring efficient exposure of catalytic sites. Electrochemical analyses reveal that the A/C-NiCo 2 O 4 /NF catalyst benefits from the synergistic integration of the high electrical conductivity inherent to the crystalline domains and the superior intrinsic catalytic activity of the amorphous regions. In contrast, its fully crystalline counterpart (C-NiCo 2 O 4 /NF) exhibits limited surface reconstruction and inferior EOR performance, underscoring the critical role of amorphization in facilitating catalytic enhancement. The unique amorphous/crystalline interface in A/C-NiCo 2 O 4 /NF facilitates electron redistribution, forming electron-deficient amorphous domains that promote OH¯ adsorption. Furthermore, a higher concentration of high-valen...