Electrochemically stable black TiO₂ composed of Ti³⁺ ions and oxygen vacancies is successfully synthesized by a facile and economic sol–gel method followed by calcination in nitrogen atmosphere at 400 °C for 2 h. Several physicochemical techniques are probed to validate the desired state of the obtained material. The material is formed in a pure state with an average size of 10 nm. The electrochemical studies are conducted for its use as negative electrode for Li-ion batteries. At high current rate of 5 C, the electrodes deliver a high discharge capacity of 226 mA h g⁻¹ even after 150 cycles. Similarly, the electrodes also deliver discharge capacities of 197 and 153 mA h g⁻¹ at current rates of 7 C and 10 C, respectively. The robust electrochemical properties of black TiO₂ including large specific capacities at high current rates and high stability are ascribed to the formation of defective structure, conductive Ti³⁺ ions and oxygen vacancies.

中文翻译：

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黑色TiO 2作为锂离子电池稳定高倍率负极的稳健电化学

通过简便，经济的溶胶-凝胶法成功地合成了由Ti ³⁺离子和氧空位组成的电化学稳定的黑色TiO ₂，然后在氮气氛中于400°C煅烧2 h。探索了几种物理化学技术以验证所获得材料的所需状态。该材料以纯态形成，平均尺寸为10 nm。对其进行电化学研究以将其用作锂离子电池的负极。在5 C的高电流速率下，即使经过150次循环，电极仍可提供226 mA hg ^-1的高放电容量。类似地，电极还提供197和153 mA hg ^-1的放电容量分别以7 C和10 C的电流速率。黑色TiO ₂的强大电化学性能包括高电流速率下的大比容量和高稳定性，这归因于缺陷结构的形成，导电Ti ³⁺离子和氧空位的形成。