Tuning B4C crystal growth with polyol-modified gel precursors and assessing needle-like B4C for energy storage

Abstract

This article introduces an innovative approach to tailor the morphology of boron carbide (B4C) particles by adjusting the polyols in polymeric precursors. This modification enables the control of the C/B2O3 ratio of the precursor and the formation of H3BO3 crystals on its surface. These H3BO3 crystals play a crucial role in inducing the growth of nano boron carbide particles with a high aspect ratio. Scanning electron microscopy (SEM) images depict that precursors lacking the ethylene glycol component yield polyhedral-equiaxed B4C particles. Conversely, the use of precursors containing 50 mol% ethylene glycol and the lowest C/B2O3 ratio leads to the formation of B4C particles with a needle-like morphology. Moreover, the influence of particle morphology on the electrochemical properties of boron carbide was investigated, and the potential of boron carbide in energy storage devices was delved into, with the needle-like boron carbide particles showed superior performance a specific capacitance of 139.7 F/g at 1 A/g and also showcased a long-term stability of 66 % after 5000 cycles.