Key Laboratory for Colloid and Interface Chemistry of State Education Ministry, School of Chemistry and Chemical Engineering, Shandong University , Jinan 250100, P. R. China.
Hefei National Laboratory for Physical Science at Microscale, Department of Chemistry, University of Science and Technology of China , Hefei 230026, P. R. China.
ACS Appl Mater Interfaces. 2017 Dec 20;9(50):43648-43656. doi: 10.1021/acsami.7b13382. Epub 2017 Dec 8.
Flower-like assembly of ultrathin nanosheets composed of anatase and bronze TiO embedded in carbon is successfully synthesized by a simple solvothermal reaction, followed with a high-temperature annealing. As an anode material in sodium-ion batteries, this composite exhibits outstanding electrochemical performances. It delivers a reversible capacity of 120 mA h g over 6000 cycles at 10 C. Even at 100 C, there is still a capacity of 104 mA h g. Besides carbon matrix and hierarchical structure, abundant interfaces between anatase and bronze greatly enhance the performance by offering additional sites for reversible Na storage and improving the charge-transfer kinetics. The interface enhancements are confirmed by discharge/charge profiles, rate performances, electrochemical impedance spectra, and first-principle calculations. These results offer a new pathway to upgrade the performances of anode materials in sodium-ion batteries.
通过简单的溶剂热反应和高温退火，成功合成了由锐钛矿和青铜 TiO 嵌入碳中的超薄纳米片组成的花状组装体。作为钠离子电池的阳极材料，该复合材料表现出优异的电化学性能。在 10 C 下，经过 6000 次循环后，可逆容量为 120 mA h g。即使在 100 C 下，仍有 104 mA h g 的容量。除了碳基体和分层结构外，锐钛矿和青铜之间丰富的界面通过提供更多的可逆 Na 存储位点和提高电荷转移动力学来极大地提高了性能。通过放电/充电曲线、倍率性能、电化学阻抗谱和第一性原理计算证实了界面增强。这些结果为提升钠离子电池阳极材料的性能提供了新途径。
