过渡金属单原子/碳界面氧催化剂的制备及其锌空电池性能研究

The oxygen reduction and oxygen evolution reaction are the keys of Zn-air battery, but their intrinsic kinetics are relatively slow, and it is necessary to accelerate the reaction by high efficiency bi-functional oxygen catalyst. As one of the best oxygen catalysts of Zn-air batteries, precious metal (Pt/RuO2) still suffer some shortcomings such as their limited resource, low stability and inefficient utilizing issue, which limit the development of Zn-air batteries. Transition metal single atom/carbon interface oxygen catalysts, which own ultrahigh atom utilization, low coordination number and strong metal-carbon interfacial interaction, provide a new direction for the research of high efficiency oxygen catalysts. In this project, based on the unique chemical and physical properties of metal single atom catalysts, we will provide kinds of novel transition metal single atom/carbon interface oxygen catalysts to improve the properties of Zn-air batteries by new refluxing etching and UV-assisted low temperature reduction methods. By optimizing the micro-structure of carbon support, loading of metal single atoms, and strong interaction between carbon supports and different transition metal atoms, we could reveal the structure-function relationship between the microstructure, the interface effect of single atomic metal/carbon substrates and electro-catalytic performance. The researches supported by this project will provide scientific basis and experimental guidance for researching the safety, long life, high energy and flexible Zn-air battery.

氧还原和氧析出反应是可充式锌空电池的关键步骤，但其本征动力学速度比较缓慢，需要高效双功能氧催化剂加快反应进行。贵金属（Pt/RuO2）是目前最有效的锌空电池阴极氧催化剂，但其价格昂贵、利用率低且稳定性差等问题严重制约了锌空电池发展。廉价的过渡金属单原子催化剂，因具有超高金属原子利用率、低配位数和金属-载体强相互作用等优势，为高效氧催化剂的设计和催化机理的探究提供了一个新的思路。基于金属单原子催化剂独特的化学和物理属性，本项目拟探索回流刻蚀和紫外光辅助低温还原等新策略制备系列新型过渡金属单原子/碳界面催化剂提升锌空气电池的性能。通过优化载体结构、金属单原子载量、过渡金属单原子与载体之间界面相互作用，并揭示催化剂微观结构、活性位点密度和界面效应与电催化性能之间的构效关系，为研发安全、长寿命、高能量的柔性锌空电池提供科学依据和实验指导。

廉价的过渡金属单原子催化剂，因具有超高金属原子利用率、低配位数和金属-载体强相互作用等优势，成为最具潜力的氧催化剂。本项目主要探索了制备新型过渡金属单原子/碳界面催化剂的新策略，优化载体结构、金属单原子载量、过渡金属单 原子与载体之间界面相互作用，并揭示催化剂微观结构、活性位点密度和界面效应与电催化性能之间的构效关系，最终提升锌空气电池的性能。本项目主要取得了如下重要进展：（1）探索了几种制备具有电化学优势的富缺陷碳载体材料的方法，具体研究了高性能碳材料的微观形貌、比表面积、孔结构分布、导电性、缺陷度等与电化学性能之间的关系，并初步实现了其在电化学领域中的高性能应用。（2）开发了系列过渡金属单原子催化剂材料的制备方法，如植酸刻蚀法、硼酸刻蚀法、氨水诱导法等，实现了系列金属单原子/碳界面催化剂的制备。对比了不同类型的金属单原子催化剂的催化性能变化，并将该性能变化趋势与碳载体、金属元素种类、过渡金属键和类型等因素进行分析处理，总结出制约氧催化剂性能的关键因素。选择性能较好的催化剂材料，构建膜电极，最终成功搭建了锌空气电池。该项目的开展为研发安全、长寿命、高能量的柔性锌空电池提供了一定的基础。