Lin Yong-Mao, Klavetter Kyle C, Heller Adam, Mullins C Buddie
†McKetta Department of Chemical Engineering, ‡Department of Chemistry and Biochemistry, §Center for Electrochemistry, and ⊥Texas Materials Institute and Center for Nano- and Molecular Science, University of Texas at Austin, 1 University Station, C0400 Austin, Texas 78712-0231, United States.
J Phys Chem Lett. 2013 Mar 21;4(6):999-1004. doi: 10.1021/jz4003058. Epub 2013 Mar 12.
Amorphous GeO2 nanoparticles were prepared via a surfactant-assisted hydrothermal process. The effect of the reaction temperature and the surfactant concentration on the morphology of GeO2 particles were investigated. Particles of less than 300 nm were obtained when using 1,2-diaminopropane surfactant in a synthesis carried out at 180(◦)C. The synthesized germanium oxide nanoparticles were evaluated for their utility as the active anode material in Li-ion batteries. The electrode prepared with this material exhibited a stable capacity ∼600 mAh g(-1) at 0.2 C rate for up to 150 cycles in a conventional electrolyte containing ethylene carbonate (EC). The cyclability of the GeO2 nanoparticle electrode was further improved by using a fluorinated ethylene carbonate (FEC) based electrolyte, which showed capacities greater than 600 mAh g(-1) and retained more than 96% of their capacity after 500 cycles at 0.2 C rate. The effect of different electrolyte systems was studied by using electrochemical impedance spectroscopy and electron microscopy.
通过表面活性剂辅助水热法制备了非晶态GeO₂纳米颗粒。研究了反应温度和表面活性剂浓度对GeO₂颗粒形貌的影响。在180℃下使用1,2 - 二氨基丙烷表面活性剂进行合成时，获得了小于300nm的颗粒。对合成的氧化锗纳米颗粒作为锂离子电池活性负极材料的效用进行了评估。用这种材料制备的电极在含有碳酸亚乙酯（EC）的传统电解质中，在0.2C倍率下循环150次时表现出稳定的容量~600 mAh g⁻¹。通过使用基于氟代碳酸亚乙酯（FEC）的电解质进一步提高了GeO₂纳米颗粒电极的循环性能，该电解质在0.2C倍率下500次循环后显示出大于600 mAh g⁻¹的容量，并保留了超过96%的容量。通过电化学阻抗谱和电子显微镜研究了不同电解质体系的影响。
