可充镁电池正极材料PTMA/石墨烯

本文制备了聚4-甲基丙烯酸-2,2,6,6-四甲基哌啶-1-氮氧自由基酯(PTMA)/石墨烯纳米复合材料,并报道了其作为可充镁电池正极材料的电化学性能.通过傅里叶变换红外(FTIR)光谱、扫描电镜(SEM)、透射电镜(TEM)表征复合材料的结构和形貌;循环伏安和恒电流充放电测试其电化学性能.粒径10 nm左右的PTMA颗粒分散在具有导电作用的石墨烯表面;在"一代"电解液Mg(AlCl2BuEt)2/四氢呋喃(THF)(0.25 mol L-1)中,22.8mA g-1充放电电流密度下,PTMA/石墨烯复合材料的起始放电容量可达到81.2 mAh g-1.研究结果表明,含有自由基的有机化合物可以作为可充镁电池的一类新型正极材料,可以进一步通过使用具有高氧化分解电压的电解液来提高其放电容量.

PTMA/Graphene as a Novel Cathode Material for Rechargeable Magnesium Batteries

We report the synthesis of a poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA)/graphene nanocomposite in which graphene is used as a support for improving electronic conductivity. The structure and morphology of the nanocomposite were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). These results reveal that a graphene surface is decorated by nanoparticles of PTMAwith an average size of 10 nm. The electrochemical performance of the PTMA/graphene composite as a cathode material in rechargeable magnesium batteries was investigated using cyclic voltammetry and galvanostatic charge/discharge techniques. In a "first generation" electrolyte Mg(AlCl₂BuEt)₂/tetrahydrofuran (THF) (0.25 mol·L^-1), the material exhibits an initial discharge capacity of 81.2 mAh·g^-1 at 22.8 mA·g^-1. Further studies will focus on improving the capacity using electrolytes with a wider electrochemical window.