This paper describes a simple, reproducible, and scalable procedure for the preparation of a SiO 2 -containing supercapacitor with high cycle stability. A carbon mesoporous material (CMM) with a high specific surface area, CMK-3, was adopted as an electric double-layer capacitor (EDLC) active material for the preparation of electrodes for the supercapacitor. The optimized SiO 2 content decreased as the microsphere diameter decreased, and the optimal specific capacitance was obtained with 6 wt % SiO 2 microspheres (100 nm size). The capacitance improved from 133 to 298 F/g. The corresponding capacitance retention rate after 1000 cycles increased from 68.04 to 91.53%. In addition, the energy density increased from 21.05 to 26.25 Wh/kg with a current density of 1 A/g. Finally, similar results based on active carbon, CeO 2 /CMK-3, and graphene/CNT/ MnO v composite electrodes demonstrated that the proposed method exhibits wide compatibility with diverse electrode materials.

A composite of highly dispersed Pt-RuO u-SnO v nanoparticles (NPs) on a mesoporous carbon CMK-3 framework was synthesized. The resulting composites of Pt, RuO u , SnO v , and CMK-3 were designated P w R x S y /C3, and their microstructures and compositions were systematically characterized using a variety of techniques. The Pt-based NPs have average particle sizes of 2-8 nm and were well dispersed in the pore channels of the CMK-3 host. The methanol oxidation reaction (MOR) activity of the catalysts was investigated as a function of the Sn mass fraction. The electrochemical activity for the MOR improved with increasing Sn content in the Pt-Ru-Sn/CMK-3 composite. In short, MOR activity, CO tolerance, long-term stability, cyclic durability, and cost performance of our proposed composition were significantly improved, which renders efficient routes to developing catalysts for direct methanol fuel cells.

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