Zinc ferrite nanoparticles as electrode material for supercapacitors

Abstract In the realm of sustainable and renewable nanotechnology, supercapacitors have appeared as the dominant solution for energy conversion and storage. Ferrites while being widely explored in magnetic, electronic and microwave devices, are now being explored for applications in energy storage devices due to possibilities of achieving fast and reversible surface Faradic reactions. In this perspective, a simple and inexpensive chemical co-precipitation method was used to synthesize ultra small ZnFe2O4 nanoparticles (NP). The ZnFe2O4 NP as electrode material show gravimetric capacitance of 186.6 Fg−1 at current density of 1 Ag−1 in 1M H2SO4. Furthermore, the ZnFe2O4 NP based electrode show exceptional capacitive retention of 98% over 1000 cycles at a current density of 3 Ag−1. An asymmetric ZnFe2O4 NP//NiO NP device was fabricated, which achieved a power density of 302.3 WKg−1 at current density of 1.5 Ag−1 and energy density of 14.85 WhKg−1. After 1500 cycles, the device demonstrated capacity retention of 99.4% at 1.5 Ag−1 in the long-term stability testing with 100% efficiency. Our study suggests that ZnFe2O4 NP are promising as a material for future energy storage applications.