ACS Appl Mater Interfaces. 2018 Jun 27;10(25):21281-21290. doi: 10.1021/acsami.8b03736. Epub 2018 Jun 13.
To enable lithium-oxygen batteries for practical applications, the design and efficient synthesis of nonprecious metal catalysts with high activity and stable structural properties are demanded. The objective is to accelerate the sluggish kinetics of both oxygen reduction reaction and oxygen evolution reaction by facilitating electronic/ionic transport and improving oxygen diffusion in a porous structure. In this study, high-surface-area and porous cobalt phosphide (CoP) nanosheets are synthesized via an environmentally safe hydrothermal method, where red phosphorous is used as the phosphorous source. It was found that the as-prepared CoP/acetylene black (AB) composite delivered enhanced electrochemical performances, such as high capacities of 2551 mA h g (based on the total weight of CoP and AB) or 5102 mA h g (based on the weight of CoP or AB) and a good cycle life of more than 1800 h (132 cycles) in lithium-oxygen battery. The rational design of the CoP/AB porous oxygen electrode structure provides sufficient accessible reaction sites and a short diffusion path for electrolyte penetration and diffusion of O.
为了使锂-氧电池能够实际应用，需要设计和高效合成具有高活性和稳定结构性能的非贵金属催化剂。目的是通过促进电子/离子传输和改善多孔结构中的氧气扩散，加速氧气还原反应和氧气析出反应的缓慢动力学。在这项研究中，通过环境安全的水热法合成了具有高表面积和多孔的钴磷化物（CoP）纳米片，其中红磷被用作磷源。研究发现，所制备的 CoP/乙炔黑（AB）复合材料在锂-氧电池中表现出增强的电化学性能，例如 2551 mA h g（基于 CoP 和 AB 的总重量）或 5102 mA h g（基于 CoP 或 AB 的重量）的高容量和超过 1800 h（132 个循环）的良好循环寿命。CoP/AB 多孔氧气电极结构的合理设计为电解质渗透和 O 扩散提供了充足的可及反应位点和短的扩散路径。
