Highly porous carbon materials filled with gold and manganese oxide nanoparticles for electrochemical use

Abstract The reduction of aqueous solutions of precursors (HAuCl 4 and KMnO 4 ) by the carbon matrix was used to synthesize nanostructured composites based on highly porous carbon materials that are filled with Au or Mn x O y nanoparticles. The resulting composites were characterized using a complex of complementary physicochemical methods (XRD, SAXS, low-temperature nitrogen sorptometry, and CV). It was shown that at low concentrations of Au or Mn x O y the surface of matrix pores is decorated with the filler nanoparticles, which block mesopores; the role of such blocking increases with the filler content. The optimal concentration of fillers in the composites was found. A maximum capacitance of composite electrodes, which exceeds the capacitance of electrodes based on the initial matrices by a factor of 2–2.5, was observed at a gold content of 1 wt.%. Nanocomposite Au/C electrodes based on highly porous carbon material Kemerit2, which were obtained in the study, showed the highest capacitance (up to 1000 F/g). For the composite systems filled with manganese oxides, a 700 F/g capacitance of composite electrodes (at a 10 mV/s scanning rate of potential) was reached at a 2 wt.% content of manganese in the composites.