Microwave synthesis of iron foam self-supported Ag–Bi bimetallic for supercapacitor anode materials

In this study, Ag – Bi bimetallic negative electrode was prepared on Fe foam substrate through a clean and efficient one-step microwave route. The synergistic effect of Ag, Bi, and Fe endowed the electrode with a remarkable electrochemical performance. The electrode attained an impressive areal capacitance of 5.24 F cm −2 at 1 mA cm −2 in 6 M KOH. Notably, the capacitance dropped to 76% of its original capacitance after undergoing 10,000 charge-discharge cycles at 10 mA cm −2 , which indicates good stability and reliability. Furthermore, an asymmetric supercapacitor was designed and built using Ag–Bi/iron foam as the positive electrode. The device maintained an 85.3% initial capacitance through 12,000 charge-discharge cycles, while delivering good areal energy/power density (643.56 µWh cm −2 /1266.63 µW cm −2 ). This study established a fabrication strategy for high-performance anode materials, achieved an excellent balance between electrochemical efficiency and economic viability, and demonstrated substantial potential for practical application.