A flexible air electrode with excellent activity and stability is essential for flexible zinc-air batteries. In this study, we report the rational design of nitrogen-doped carbon nanotube-encapsulated Co₉S₈ nanoparticles on carbon cloth (Co₉S₈/NCNTs/CC), serving as self-supporting air electrodes for both liquid-state and flexible zinc-air batteries. The Co₉S₈/NCNTs/CC-1 exhibited a half-wave potential of 0.86 V for oxygen reduction reaction (ORR) and achieved a current density of 10 mA cm⁻² for oxygen evolution reaction (OER) at a voltage of only 1.52 V. The well-constructed nanotube on carbon cloth facilitates mass diffusion and electron transfer, while enhancing the mechanical flexibility of the material. Density functional theory (DFT) calculations suggested that the synergistic interaction between Co₉S₈ and NCNTs effectively enhanced the bifunctional electrocatalytic performance of the material. Liquid-state and flexible zinc-air batteries assembled with Co₉S₈/NCNTs/CC-1 demonstrated outstanding charge-discharge capabilities and long-term stability.

中文翻译：

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原位氮掺杂碳纳米管封装的 Co9S8 纳米颗粒作为锌空气电池的自支撑双功能空气电极


具有出色活性和稳定性的柔性空气电极对于柔性锌空气电池至关重要。在这项研究中，我们报道了氮掺杂碳纳米管封装的 Co₉S₈ 纳米颗粒在碳布 （Co₉S₈/NCNTs/CC） 上的合理设计，作为液态和柔性锌空气电池的自支撑空气电极。Co₉S₈/NCNTs/CC-1 在氧还原反应 （ORR） 中表现出 0.86 V 的半波电位，在仅 1.52 V 的电压下，析氧反应 （OER） 的电流密度为 10 mA ^cm-2。碳布上结构良好的纳米管促进了质量扩散和电子转移，同时增强了材料的机械柔韧性。密度泛函理论 （DFT） 计算表明，Co₉S₈ 和 NCNTs 之间的协同作用有效地增强了材料的双功能电催化性能。使用 Co₉S₈/NCNTs/CC-1 组装的液态和柔性锌空气电池表现出出色的充放电能力和长期稳定性。