Enhanced supercapacitor performance using self-assembled silver nanowire electrodes

Using a controlled self-assembly approach, this study demonstrates the successful fabrication of electrodes based on silver nanowires (AgNWs), which are promising materials for flexible energy storage systems. Glass substrates functionalized with (3-aminopropyl)triethoxysilane (APTES) are coated with AgNW films for 4, 8, and 16 h. The morphological, structural, and electrochemical properties of these films are subsequently evaluated. X-ray diffraction (XRD) analysis reveals high crystalline phase purity and a face-centered cubic (fcc) structure in the synthesized AgNWs. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) characterizations indicate that a uniform nanowire network and optimal surface roughness are achieved with an 8-hour coating time. Four-point probe measurements confirm enhanced electrical conductivity, particularly in the AgNWs@8 h sample. Electrochemical performance is assessed using a two-electrode system in 6 M potassium hydroxide (KOH) electrolyte. The AgNWs@8 h electrodes exhibit the highest specific capacitance (318.84 F/g), energy density (102.03 Wh/kg), and power density (1119.68 W/kg) at 1 A/g in a symmetric two-electrode configuration. These results demonstrate that oriented AgNW structures offer a high-performance, scalable, and low-temperature alternative to conventional supercapacitor electrodes.