Hierarchical porous ZnCo₂O₄ nanosheets and ZnCo₂O₄‐coated reduced graphene oxide (ZnCo₂O₄/rGO) were synthesized by the hydrothermal method followed by the annealing process. The composition of materials was proved by X‐ray electron spectroscopy and X‐ray photoelectron spectroscopy. The size and morphology of the as‐prepared samples were evaluated by scanning electron microscopy and transmission electron microscopy. The result showed ZnCo₂O₄ nanosheets with porous morphology and a sheet thickness of about 5 nm was well synthesized. The electrochemical tests used to prove the catalytic performance of the prepared catalysts were cyclic voltammetry and impedance spectroscopy, and the analysis was performed in alkaline environments. The electrochemical investigations on ZnCo₂O₄ and ZnCo₂O₄/rGO showed the rGO has an effective role in electrooxidation of methanol in alkaline media. In addition to the synergic effect between Zn and Co, the synergistic effect between ZnCo₂O₄ (make active sites for adsorption of methanol) and rGO (provide more conductivity and make more sites by preventing from the agglomeration of ZnCo₂O₄) has an important role for this excellent performance. The polarization curves of ZnCo₂O₄/rGO showed a maximum power density of 24.3 mW cm⁻², which proved its potential capability for the direct methanol fuel cell.

中文翻译：

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ZnCo2O4和rGO的分层混合体，作为甲醇氧化反应的重要电催化剂：合成，表征和电催化性能

通过水热法和退火工艺合成了多层多孔ZnCo ₂ O ₄纳米片和ZnCo ₂ O ₄包覆的还原氧化石墨烯（ZnCo ₂ O ₄ / rGO ）。通过X射线电子光谱和X射线光电子光谱证明了材料的成分。通过扫描电子显微镜和透射电子显微镜评估所制备样品的大小和形态。结果表明ZnCo ₂ O ₄良好地合成了具有多孔形态和约5nm的片厚度的纳米片。用于证明制备的催化剂的催化性能的电化学测试是循环伏安法和阻抗谱，并且在碱性环境下进行分析。对ZnCo ₂ O ₄和ZnCo ₂ O ₄ / rGO的电化学研究表明，rGO在碱性介质中对甲醇的电氧化具有有效的作用。除了Zn和Co的协同作用外，ZnCo ₂ O ₄（使甲醇吸附的活性位点）和rGO（防止ZnCo的团聚提供更多的电导率和更多的位点）之间的协同作用₂ O ₄）对于这种出色的性能起着重要作用。ZnCo ₂ O ₄ / rGO的极化曲线显示最大功率密度为24.3 mW cm ^-2，这证明了其对直接甲醇燃料电池的潜在能力。