Effect of Li2CoMn3O8 Nanostructures Synthesized by a Combustion Method on Montmorillonite K10 as a Potential Hydrogen Storage Material

摘要

This paper outlines new design nanocomposites (Li2CoMn3O8/K10) for electrochemical hydrogen storage with an emphasis on the optimal conditions to achieve higher performance. Li2CoMn3O8/K10 nanocomposites were fabricated by loading different ratios of the Li2CoMn3O8 (5%, 10%, and 20%) inside the montmorillonite K10. Electrochemical properties of the samples montmorillonite K10, Li2CoMn3O8, and the respective nanocomposites were studied by chronopotentiometry charge-discharge techniques in alkaline medium. The Li2CoMn3O8 nanostructures were synthesized by a facile combustion method in the presence of various carboxylic acids as fuel and capping agents. The influence of carboxylic acids on the size, morphology, and homogeneity of the samples was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and Fourier transform infrared (FT-IR) were applied to investigate the purity and chemical compositions of the samples. The electrochemical hydrogen storage performances of the samples were identified on the basis of a discharge capacity at the 15th cycle of 1041 mAhg(-1) for pristine K10 which increases with a raise in ratio of Li2CoMn3O8. The discharge capacity for K10 by adding 20 wt % nanoparticles rises to 1302 mAhg(-1). Our results indicate that modifying by means of Li2CoMn3O8 nanoparticles can be a promising low-cost method to improve electrochemical performance of various hydrogen storage materials including montmorillonite K10.