Su Kai, Tang Chenxia, Li Chunyue, Weng Shijie, Xiang Yong, Peng Xiaoli
School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu, 611731, Sichuan, People's Republic of China.
Frontier Center of Energy Distribution and Integration, Tianfu Jiangxi Lab, Huoju Avenue, Futian Sub-District, Jianyang City, Chengdu, 641419, Sichuan, People's Republic of China.
Discov Nano. 2024 Dec 24;19(1):213. doi: 10.1186/s11671-024-04177-4.
LiTiO (LTO) batteries are known for safety and long lifespan due to zero-strain and stable lattice. However, their low specific capacity and lithium-ion diffusion limit practical use. This study explored modifying LTO through yttrium doping by hydrothermal method to form LiYTiO nanoparticles. This approach optimized electron and ion transport, markedly enhancing rate and cycle performance. XRD and TEM revealed that Y addition increased interplanar distance of LTO and widened Li transport pathways. XPS indicated that Y doping augmented the oxygen vacancy concentration and Ti content. UV tests demonstrated a band gap reduction from 3.72 eV to 2.94 eV, accompanied by enhanced electronic conductivity. EIS tests showed lithium-ion diffusion coefficient remarkably increased to 1.27 × 10 cm s The initial discharge capacity of LiYTiO at 1 A g reached 198.9 mAh g and retained 89.3% capacity after 1000 cycles. At 6 A g, the discharge capacity was 161.1 mAh g, while at an ultra-high current density of 20 A g, it reached 78.8 mAh g, highlighting its robust rate performance. The yttrium-doped and nano-morphology stabilizes the LTO lattice, enhancing rate performance and cycling stability. This study reveals that LTO has the potential to be used in the high-energy fast-charging storage market.
锂钛氧化物(LTO)电池因其零应变和稳定的晶格结构而以安全性高和寿命长著称。然而,其低比容量和锂离子扩散限制了实际应用。本研究探索了通过水热法进行钇掺杂来改性LTO,以形成LiYTiO纳米颗粒。这种方法优化了电子和离子传输,显著提高了倍率性能和循环性能。X射线衍射(XRD)和透射电子显微镜(TEM)表明,钇的加入增加了LTO的晶面间距,拓宽了锂传输通道。X射线光电子能谱(XPS)表明,钇掺杂增加了氧空位浓度和钛含量。紫外测试表明带隙从3.72电子伏特降低到2.94电子伏特,同时电子导电性增强。电化学阻抗谱(EIS)测试表明锂离子扩散系数显著增加到1.27×10⁻⁸厘米²秒⁻¹。LiYTiO在1 A g⁻¹时的初始放电容量达到198.9 mAh g⁻¹,在1000次循环后仍保留89.3%的容量。在6 A g⁻¹时,放电容量为161.1 mAh g⁻¹,而在20 A g⁻¹的超高电流密度下,达到78.8 mAh g⁻¹,突出了其优异的倍率性能。钇掺杂和纳米形态稳定了LTO晶格,提高了倍率性能和循环稳定性。本研究表明LTO有潜力应用于高能快充储能市场。