Improved high-rate performance and cycling stability of 1D LiFePO4 nanorods by a facile annealing process

To alleviate the main limitations of lithium ion diffusion rate and poor electronic conductivity for LiFePO4 cathode material, it is desirable to synthesize nano-size LiFePO4 material due to its enhanced electronic and lithium ion transport rates and thus an improved high-rate performance. However, our previous synthesized LiFePO4 nanorods only exhibited low high-rate and slightly unstable cycle performance. Possible reasons are the poor crystallization and Fe2+ oxidation of LiFePO4 nanorods prepared by hydrothermal method. In this paper, LiFePO4 nanorods were simply dealt with at 700 ℃ for 4 h under the protection of Ar and H2 mixture gas. The electrochemical properties of LiFePO4/Li cells were investigated by galvanostatic test and cyclic voltammetry(CV). The experimental results indicated that the annealed LiFePO4 nanorods delivered an excellent cycling stability and obviously improved capacity of 150 mA·h·g-1 at 1C, and even 122 mA·h·g-1 at 5C.     

溶胶-凝胶薄膜的制备和应用

概述了溶胶—凝胶薄膜的制备方法和在各个领域的应用。并对溶胶—凝胶薄膜制备的基本原理、制备过程中薄膜质量的影响因素和存在的问题进行了探讨和总结。     

溶胶凝胶涂层技术的现状与展望

本文主要综述了各种溶胶凝胶涂层技术的简单机理与工艺,其中包括浸渡涂层技术、喷雾涂层技术、流动涂层技术、自旋涂层技术、毛细管涂层技术、滚动涂层技术等,并对涂层与基体的结合做了简要讨论。     

Self-assembled synthesis of porous TiO2 film on the electrophoretic-deposited titanate nanoribbon film

The porous TiO₂ film was self-assembled on the surface of electrophoretic-deposited titanate nanoribbon film without the addition of templates by using TiF₄ as the precursor.It was found that the hydrolysis of TiF₄ was accompanied with the self-assembly processes of TiO₂ nanoparticles on the surface of electrophoretic-deposited titanate nanoribbon film,resulting in the formation of porous TiO₂ structures.Titanate nanoribbon film was demonstrated to provide the active sites for the effective self-assembly of porous TiO₂ nanostructures owing to a large amount of hydroxyl groups.Compared with the nonporous TiO₂ film,the prepared porous TiO₂ films obviously showed an enhanced photocatalytic activity,which could be attributed to the rapider diffusion and more efficient transport of various reactants and products during photocatalytic reaction in the porous structures.     

无机空心微球的化学诱导自转变制备及其在光催化中的应用

近年来,粒径在纳米至微米级的空心微球作为一类性能优良的新型功能材料已经广泛应用于化学、生物医药和新材料等领域中,如被用作催化剂载体、控制药物释放、色谱分离、微化学反应器、环境敏感生物分子的保护等,有关空心微球的研究已成为化学和新材料科学等领域的研究热点.