Robust structural stability and performance-enhanced asymmetric supercapacitors based on CuMoO4/ZnMoO4 nanoflowers prepared via a simple and low-energy precipitation route

Abstract

A detailed understanding of synergistic effects is very important for obtaining high-performance supercapacitor electrodes. A facile, swift and low-energy precipitation route has been employed to design CuMoO4/ZnMoO4 nanoflower arrays and subsequently explore their structural and electronic characteristics. Remarkably, CuMoO4/ZnMoO4-based supercapacitor exhibited superior specific capacitance of 840 F/g compared to 203 F/g and 460 F/g for CuMoO4 and ZnMoO4, respectively, at 2 A/g. The composite showed a remarkable long cycle lifetime with a cycling efficiency of 93.8 % after 5000 cycles. Moreover, an asymmetric CuMoO4/ZnMoO4//AC supercapacitor with a voltage of 1.5 V delivered a specific capacitance of 186 F/g at 1.5 A/g, specific energy of 34.8 Wh/kg at specific power of 472 W/kg and retained approximately 90% of the original capacitance after 8000 cycles. The outstanding supercapacitive performance is ascribed to the unique nanoflower design, low solution resistance of 0.28 ohm, and the synergy from the single components.