Electrochemical investigation of -MnO2 octahedral microparticles decorated micro-sized silicon

Charge storage study using beta-MnO2 octahedrons has not been studied due to its relatively lower capacitive property. This work presents the charge storage capacity of truncated beta-MnO2 octahedral microparticles decorated onto micro-sized silicon (mSi) prepared by simple cost-effective and environment-friendly hydrothermal method. The designed truncated MnO2 octahedrons- mSi observed through SEM, when structurally characterized using XRD and Raman spectroscopy revealed the beta phase of MnO2. The 3-electrode cell-based charge storage study demonstrated a specific capacitance of 353 F g-1 at 5 mV s-1 with an equivalent series resistance (ESR) of 10.29 ohms. The CV curves revealed a pseudocapacitive charge storage behavior with reversible Faradaic reactions and confirmed through charge storage kinetics evaluation using power law. An attractive energy density of 97.75 Wh kg-1 and 1700 W kg-1 power density was displayed by the electrode at 1.7 A g-1 current density which is comparable to existing literature in the field. This study not only opens the possibility of exploring the practical applicability of the enhanced charge storage capability using the proposed design but also stimulates further research on doped beta-MnO2 with suitable conductive material to reduce ESR. In addition, the role of mSi can be further explored to provide enhanced energy storage applications.