Du Guifen, Gong Piyu, Cui Chuansheng, Wang Lei, An Changhua
Department of Chemistry, Liaocheng University, Liaocheng 252059, China.
School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, China.
Nanomaterials (Basel). 2024 Aug 23;14(17):1378. doi: 10.3390/nano14171378.
The pseudocapacitive effect can improve the electrochemical lithium storage capacity at high-rate current density. However, the cycle stability is still unsatisfactory. To overcome this issue, a multivalent oxide with a carbon coating represents a plausible technique. In this work, a CuO-CuO@C composite has been constructed by a one-step bilayer salt-baking process and utilized as anode material for lithium-ion batteries. At a current density of 2.0 A g, the as-prepared composite delivered a stable discharge capacity of 431.8 mA h g even after 600 cycles. The synergistic effects of the multivalence, the pseudocapacitive contribution from copper, and the carbon coating contribute to the enhanced electrochemical lithium storage performance. Specifically, the existence of cuprous suboxide improves the electrochemical conductivity, the pseudocapacitive effect enhances the lithium storage capacity, and the presence of carbon ensures cycle stability. The testing results show that CuO-CuO@C composite has broad application prospects in portable energy storage devices. The present work provides an instructive precedent for the preparation of transition metal oxides with controllable electronic states and excellent electrochemical performance.
赝电容效应可以在高电流密度下提高电化学锂存储容量。然而，循环稳定性仍然不尽人意。为了克服这个问题，一种具有碳涂层的多价氧化物代表了一种可行的技术。在这项工作中，通过一步双层盐焙烧工艺构建了CuO-CuO@C复合材料，并将其用作锂离子电池的负极材料。在2.0 A g的电流密度下，即使经过600次循环，所制备的复合材料仍能提供431.8 mA h g的稳定放电容量。多价性、铜的赝电容贡献以及碳涂层的协同效应有助于提高电化学锂存储性能。具体而言，氧化亚铜的存在提高了电化学导电性，赝电容效应增强了锂存储容量，碳的存在确保了循环稳定性。测试结果表明，CuO-CuO@C复合材料在便携式储能设备中具有广阔的应用前景。目前的工作为制备具有可控电子态和优异电化学性能的过渡金属氧化物提供了一个有指导意义的先例。
