Rational design of sucrose-derived graphitic carbon coated MnMoO₄ for high performance asymmetric supercapacitor

The utilization of rich chemistry originating from redox activity of manganese-based compounds has spurred an increasing interest into energy storage technologies including supercapacitors and rechargeable batteries. Engineering manganese molybdate would offer peculiar electronic properties, significantly amplify intrinsic electrochemical properties. Herein, graphitic carbon layers successfully coated around MnMoO₄ via one-pot hydrothermal approach to form crystalline microcube-shaped structure embedded carbon matrix (su-GC@MnMoO₄). Electrochemical measurements reveal, su-GC@MnMoO₄ electrode demonstrated specific capacitance of 528 F g⁻¹ at 2 A g⁻¹ and a cycling retention of 98.7 % of initial capacitance after 5000 cycles. In a two-electrode system of asymmetric supercapacitor with su-GC@MnMoO₄ as cathode and activated carbon (AC) as anode, we achieved specific energy of 35.4 W h kg⁻¹ at specific power of 223 W kg⁻¹ and 96.7 % of initial capacitance was retained after consecutive 10,000 cycles. These profound capacitive properties are ascribed to synergy between Mn redox strength and electronic-mechanical properties of sucrose derived carbon.