Ravi Soumya P, Praveen P, Sreelakshmi K V, Balakrishnan A, Subramanian K R V, Shantikumar V, Lee Y S, Sivakumar N
J Nanosci Nanotechnol. 2015 Jan;15(1):747-51. doi: 10.1166/jnn.2015.9174.
The present study reports an approach by which thin films of sucrose added olivine type LiMnPO4-Ccomposite and pristine LiMnPO4 is made by a technique of electrophoretic co-deposition in which pristine and composite samples were synthesized by a sol-gel route. These thin films with enhanced surface area is used to fabricate cathodes for rechargeable Li ion batteries. XRD confirms phase pure single crystalline orthorhombic structure. Transmission Electron Microscopy (TEM) images shows the carbon coating over LiMnPO4 and the particle size restricted in the nano regime. The presence of sp2 hybridized carbon on LiMnPO4 particles is confirmed by X-ray Photon spectroscopy (XPS). To explore the electrochemical behavior, cyclic voltammetry (CV) and cycling studies were performed. The specific capacity for LiMnPO4-C is found to be increased by 43% in comparison to the pristine LiMnPO4. It also exhibited 86% retention in capacity compared to the pristine LiMnPO4 (52%). The result indicates that a proper carbon coating can significantly improve the electronic conductivity and hence the specific capacity.
本研究报告了一种方法，通过电泳共沉积技术制备添加蔗糖的橄榄石型LiMnPO₄-C复合材料和原始LiMnPO₄的薄膜，其中原始样品和复合材料样品通过溶胶-凝胶法合成。这些具有增大表面积的薄膜用于制造可充电锂离子电池的阴极。X射线衍射（XRD）证实为纯相单晶体正交结构。透射电子显微镜（TEM）图像显示LiMnPO₄上的碳涂层以及粒径限制在纳米范围内。通过X射线光子能谱（XPS）证实了LiMnPO₄颗粒上存在sp²杂化碳。为了探究电化学行为，进行了循环伏安法（CV）和循环研究。发现LiMnPO₄-C的比容量相较于原始LiMnPO₄提高了43%。与原始LiMnPO₄（52%）相比，其容量保持率也达到了86%。结果表明，适当的碳涂层可以显著提高电子导电性以及比容量。
