Dasarathan Suriyakumar, Ali Mukarram, Jung Tai-Jong, Sung Junghwan, Ha Yoon-Cheol, Park Jun-Woo, Kim Doohun
Nano Hybrid Technology Research Center, Electrical Materials Research Division, Korea Electrotechnology Research Institute, Changwon 51543, Korea.
Department of Electro-Functionality Materials Engineering, University of Science and Technology (UST), Daejeon 305-333, Korea.
Nanomaterials (Basel). 2021 Oct 31;11(11):2924. doi: 10.3390/nano11112924.
Vertically aligned Fe, S, and Fe-S doped anatase TiO nanotube arrays are prepared by an electrochemical anodization process using an organic electrolyte in which lactic acid is added as an additive. In the electrolyte, highly ordered TiO nanotube layers with greater thickness of 12 μm, inner diameter of approx. 90 nm and outer diameter of approx. 170 nm are successfully obtained. Doping of Fe, S, and Fe-S via simple wet impregnation method substituted Ti and O sites with Fe and S, which leads to enhance the rate performance at high discharge C-rates. Discharge capacities of TiO tubes increased from 0.13 mAh cm(bare) to 0.28 mAh cm for Fe-S doped TiO at 0.5 C after 100 cycles with exceptional capacity retention of 85 % after 100 cycles. Owing to the enhancement of thermodynamic and kinetic properties by doping of Fe-S, Li-diffusion increased resulting in remarkable discharge capacities of 0.27 mAh cm and 0.16 mAh cm at 10 C, and 30 C, respectively.
通过电化学阳极氧化工艺，使用添加了乳酸作为添加剂的有机电解质，制备了垂直排列的铁、硫和铁 - 硫掺杂的锐钛矿型二氧化钛纳米管阵列。在该电解质中，成功获得了高度有序的二氧化钛纳米管层，其厚度更大，为12μm，内径约为90nm，外径约为170nm。通过简单的湿浸渍法进行铁、硫和铁 - 硫的掺杂，用铁和硫取代了钛和氧位点，这导致在高放电C倍率下倍率性能得到提高。经过100次循环后，在0.5C下，二氧化钛管的放电容量从0.13mAh/cm²（裸管）增加到铁 - 硫掺杂二氧化钛的0.28mAh/cm²，100次循环后容量保持率高达85%。由于铁 - 硫掺杂增强了热力学和动力学性能，锂扩散增加，导致在10C和30C时分别具有0.27mAh/cm²和0.16mAh/cm²的显著放电容量。
