Unique mesoporous carbon microsphere/1-D MnO2-built composite architecture and their enhanced electrochemical capacitance performance

Abstract

A new class of micro/nano composite architecture, characterized by radially grown MnO₂ nanoneedles on high specific surface area (SSA) mesoporous carbon microspheres (MCMs), is presented for the first time as electrode materials for electrochemical capacitors (ECs). This unique architecture could be considered as an omnibearing oriented 1-D nanostructure which possesses high power features for EC applications. When evaluated for electrochemical capacitance performance in a non-aqueous electrolyte, this composite architecture demonstrates improved electrochemical properties with maximum specific energy and energy density of 164 W h kg⁻¹ and 25 kW h L⁻¹, respectively. This enhanced performance could be mainly attributed to the integration of efficient double layer capacitance and tremendous pseudo-capacitance from MCMs and MnO₂. Our findings suggest that this composite architecture might be used as a promising anode material for high performance ECs.