Tailoring ZnMnO3 nanostructures: A promising strategy for high energy density asymmetric supercapacitors. Journal of Energy Storage, 85, 111069.
Year: 2024
DOI:https://doi.org/10.1016/j.est.2024.111069
In this study, we have successfully synthesized ZnMnO3 (ZMO) nanostructures with precisely controlled morphology and crystallinity through an advanced co-precipitation procedure and thoroughly investigated their electrochemical performance. Our approach introduced a novel, polymer-assisted synthesis process with sintering temperature variations (400–600 °C), leading to a phase transition from amorphous to moderate to highly crystalline spherical morphology. The nanostructures obtained by sintering at 500 °C (ZMO5) exhibited high porosity, exceptional crystallinity and a significantly enlarged specific surface area compared to existing reports. The Cyclic voltammetry and Galvano-potentiometry measurements for mass-optimized ZMO5 working electrode revealed excellent pseudo-capacitive behavior, achieving a maximum specific capacitance of 1755.31 Fg−1 at 1 Ag−1. Furthermore, ZMO5 exhibited outstanding cyclic stability, retaining about 92.4 % of its performance after 2000 cycles. To demonstrate practical utility, we constructed a solid-state asymmetric supercapacitor device using ZMO5. The device exhibited a maximum specific energy density of 182 W h kg−1 at a power density of 1800 W kg−1, and high cyclic stability of 84.67 % after 2000 cycles, showcasing its efficiency in energy storage applications.