Electrochemical synthesis of porous Ag@PANI/MWCNTs ternary composite for electrochemical and photocatalytic application

This paper presents a novel binder-free electrochemical synthesis of a porous ternary composite comprising polyaniline/multiwall carbon nanotubes decorated with silver nanoparticles (Ag@PANI/MWCNTs), which serves dual functions as a photocatalyst for methylene blue degradation and as an electrode for high-performance supercapacitors application. Various characterization techniques confirm that the synthesized Ag@PANI/MWCNTs composite exhibits excellent optical, chemical, electrical, structural, morphological, electrochemical and photocatalytic characteristics. The composite exhibits excellent electrochemical and photocatalytic efficacy attributed to its porosity, higher surface area, conductivity and rapid redox properties. Electrochemical tests reveal specific capacitance of 862 F/g, energy density of 65.78 Whkg-1, power density of 444.44 Wkg-1 and cycling stability with 79% capacitance retention even after 10,000 cycles. As a photocatalyst, the composite achieves approximately 95% degradation in 25 min with reusability up to five cycles. It also exhibits high transient photocurrent responses (0.36 mA/cm2) and a high-rate constant (0.13 min-1), confirming excellent photocatalytic activity. The synergistic effect of PANI/MWCNTs and the incorporation of Ag nanoparticles contribute to the outstanding performance of the synthesized nanocomposite. Thus, it is expected that the synthesized Ag@PANI/MWCNT is a promising ternary composite which may prove to be a noble material for photocatalytic and energy storage-related devices.