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A silicon carbide derived carbon (SiC-DC) with a high specific surface area (SSA) fabricated by chlorination of a silicon carbide derived from polysiloxane was activated by CO2. The effect of activation temperature and time on the microstructure of the activated samples was investigated by N2 sorption, XRD, SEM and TEM. Results showed that CO2 activation effectively changed the pore structure of the SiC-DC and had little impact on carbon crystallinity. The activated samples retained the morphology of the SiC powder or the non-activated SiC-DC. The SSA, total pore volume (Vtot) and micropore volume of the activated SiC-DCs all increased and the yield decreased with increasing activation temperature or time. The SSA and Vtot increased by 46.5 % (from 1 316.8 to 1 929.0 m2g−1) and 86.4 % (from 0.560 to 1.044 cm3g−1), respectively after the SiC-DC was activated at 950 °C for 2 h, mainly as a result of the increased micropore volume.

In this paper, we investigated the effect of thermal-treatment under an Ar atmosphere on the structural evolution of silicon oxycarbide-derived carbons (SiOC-DCs) by adjusting the temperature from 1200 to $$2100^{\circ }\hbox {C}$$, which will be characterized by means of $$\hbox {N}_{2}$$ adsorption, X-ray diffraction, Raman and transmission electron microscopy techniques, and studied their $$\hbox {CO}_{2}$$ capture performances. The results show that the structure of SiOC-DCs varied regularly with treatment temperature. The porosity and crystallinity of the as-received sample are almost stable when the thermal-treatment temperature is $$

In this paper, we used a novel carbide (or ceramer) as the carbon precursor and studied the effect of etching temperature on its compositional and structural evolution in chlorine condition. The ceramer produced from a commercially available polymethyl(phenyl) siloxane resin at 600 °C under nitrogen still includes some organic groups (e.g., Si H, Si CH3, Si Ar), which cannot survive in chlorine for 3 h in range of 450–900 °C. The ceramer can be completely converted to carbon while the etching temperature exceeds 600 °C. Higher ordering at elevated etching temperatures and apparent increasing of mesopores at 600 °C were observed.

The etching process of silicon carbide by dry chlorine was investigated as a function of etching temperature using a commercial available polymethyl(phenyl)siloxane resin. Results from etching rate show increasing etching temperature could lead to a change for etching mechanism from diffusion-controlling to interface reaction-controlling. The chlorination of β-SiC in this study should be managed at above 600 °C and can complete at 900 °C for 3 h. A pronounced core–shell structure was observed owing to the partial conversion. Silicon carbide derived carbons (SiC-DCs) are in highly microporosity, with single-modal pore size distributions at around 0.9 nm.