Synthesis of Ru_(0.58)In_(0.42)Oy·nH_2O nanoparticles dispersed onto poly(sodium-4-styrene sulfonate)-functionalized multi-walled carbon nanotubes and their application for electrochemical capacitors

摘要

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_(0.58)In_(0.42)O_y{dot operator}nH2O 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_xO_y{dot operator}nH_2O NPs onto their surfaces. The good dispersion of Ru_(0.58)In_(0.42)O_y{dot operator}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 319Fg~(-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 18.1Whkg~(-1), desirable power property of 1302Wkg~(-1), high electrochemical reversibility and good SC retention of 84.7%.