Influence of silver-decorated multi-walled carbon nanotubes on electrochemical performance of polyaniline-based electrodes

In this work, silver (Ag) nanoparticles were deposited on multi-walled carbon nanotubes (MWNTs) by chemical reduction while Ag-decorated MWNTs (Ag-MWNTs)/polyaniline (PANI) composites were prepared by oxidation polymerization. The effect of the Ag incorporated into the interface of the composites on the electrochemical performance of the MWNTs/PANI was investigated. It was found that highly dispersed Ag nanoparticles were deposited onto the MWNTs, and the Ag-MWNTs were successfully coated by PANI. According to cyclic voltammograms, the Ag-MWNTs/PANI exhibited significantly increased electrochemical performances compared to MWNTs/PANI and the highest specific capacitance obtained of MWNTs/PANI and 0.15 M Ag-MWNTs/PANI was 162 F/g and 205 F/g, respectively. This indicated that Ag nanoparticles that were deposited onto the MWNTs caused an enhanced electrochemical performance of the MWNTs/PANI due to their high electric conductivity, which resulted in an increase of the charge transfer between the MWNTs and PANI by a bridge effect.

Graphical AbstractThe current density of MWNTs/PANI increased with increasing the Ag concentration due to the bridge effect of Ag nanoparticles incorporated between MWNTs and PANI.Figure optionsDownload as PowerPoint slideHighlights
► We fabricated the silver nanoparticle decorated MWNTs/PANI composites.
► Ag-MWNTs/PANI showed enhanced electrical conductivity compared to MWNTs/PANI.
► Specific capacitance (205 F/g) of Ag-MWNTs/PANI was higher than that of MWNTs/PANI.
► Ag nanoparticles serve as catalytic materials at interface between MWNTs and PANI.