Hexamine stabilized ultrafine silver-based prussian blue analogues for electrochemical capacitor application: Integration and performance in rectifier circuit

Electrochemical capacitors have attracted considerable research interest as promising energy-storage devices owing to their high-power density, environmentally benign nature, and long cycle life, making them suitable for a broad range of modern energy-storage applications. In this work, an asymmetric electrochemical capacitor was successfully fabricated employing silver ferrocyanide as cathode material, which exhibited pronounced Faradaic behavior, indicating that the charge storage mechanism was predominantly governed by reversible redox reactions. The organic molecule stabilized ultra-fine silver ferrocyanide particles were synthesized using a complexation mediated route. The fabricated capacitor exhibited a maximum specific capacity of 128 C/g at a current density of 0.3 A/g, indicating efficient charge storage and utilization at relatively low current rates. The device exhibited a maximum energy density of 45 Wh/kg at 0.3 A/g and power density of 3.0 kW/kg −1 at 2.0 A/g. Importantly, the capacitor demonstrated excellent electrochemical durability, retaining approximately 90% of its initial capacity after 5000 charge-discharge cycles. The fabricated capacitor was integrated into a half-wave rectifier circuit, where it efficiently rectified the AC input and functioned as a filtering element to convert the pulsating signal into a smoother DC output through charge-discharge cycles.