Nanoporous carbon hybrids derived from polymethylsilsequioxane for ultracapacitor electrodes

Abstract

A nanoporous carbon hybrid with high specific surface area (SSA) and pore volume was processed in a novel two-step approach using nanocarbon and a commercial preceramic polymer. First, nanocarbon was coated with a methylsilsesquioxane based preceramic polymer, crosslinked, and pyrolyzed to obtain silicon oxycarbide (SiOC) coated nanocarbon hybrid. Further, selective etching of the SiO 2 nanodomains from the SiOC coating in the ceramic-carbon hybrid resulted a nanoporous carbon materials with excellent SSA of 1400 m 2 g −1 , and pore size distribution in the range of 1–4 nm. Preliminary investigations on the synthesized carbon hybrid with cyclic voltammetry exhibited typical rectangular voltammogram without any faradaic contribution, and high specific capacitance of 227 F g −1 at a scan rate of 20 mV s −1 . • A nanoporous carbon hybrid with excellent specific surface area (SSA) and pore volume was processed in a novel two-step approach using nanocarbon and polymethylsilsesquioxane preceramic polymer. • The SSA of the hybrid was 1400 m 2 g −1 and pore volume of 0.84 cm 3 g −1 with hierarchical porosity in microporous (<2 nm) and lower mesoporous (2–4 nm) range. • Preliminary investigations with cyclic voltammetry exhibited almost rectangular voltammogram and clear EDLC behavior without any contribution of faradaic reactions. • High specific capacitance of 227 F g −1 for the carbon hybrid was obtained at a medium range scan rate of 20 mV s −1 . • These results are bound to open up an area of exploring nanoporous materials for ultracapacitor electrodes from other commercial preceramic polymers following the process described in this manuscript.