Synthesis of Ru 0.58In 0.42O y⋅ nH 2O nanoparticles dispersed onto poly(sodium-4-styrene sulfonate)-functionalized multi-walled carbon nanotubes and their application for electrochemical capacitors

Abstract

In this work, poly(sodium-4-styrene sulfonate) (PSS)-functionalized multi-walled carbon nanotubes (FMWCNTs) were first synthesized via a polymer-assisted technique. Then, Ru 0.58In 0.42O y ⋅ nH 2O nanoparticles (NPs) were mono-dispersed onto the FMWCNTs surfaces under mild hydrothermal condition. Here, PSS with negative charge serves as a bifunctional molecule both for solubilizing and dispersing MWCNTs into aqueous solution and for tethering Ru 3+ and In 3+ to facilitate the good dispersion of Ru 1− x In x O y ⋅ nH 2O NPs onto their surfaces. The good dispersion of Ru 0.58In 0.42O y ⋅ nH 2O NPs onto FMWCNTs makes OH − ions and electrons easily contact these NPs with abundant electroactive sites, which results in a large specific capacitance (SC) of 319 F g −1 for the naocomposites. Moreover, a symmetric electrochemical capacitor (EC) is constructed by using the nanocomposites as electrodes and delivers large specific energy density of 18.1 Wh kg −1, desirable power property of 1302 W kg −1, high electrochemical reversibility and good SC retention of 84.7%.