Carbothermal synthesis of porous silicon carbide using mesoporous silicas

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• 作者：Nataliya D. Shcherban ; Svitlana M. Filonenko…
• 刊名：Journal of Materials Science
• 出版年：2017
• 出版时间：April 2017
• 年：2017
• 卷：52
• 期：7
• 页码：3917-3926
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Materials Science, general; Characterization and Evaluation of Materials; Polymer Sciences; Continuum Mechanics and Mechanics of Materials; Crystallography and Scattering Methods; Classical Mechanics;
• 出版者：Springer US
• ISSN：1573-4803
• 卷排序：52

文摘

Samples of crystal modifications of porous silicon carbide were obtained by carbothermal method using carbon precursors (sucrose, carbon) and aerosil or mesoporous silicas molecular sieves SBA-3, SBA-15, KIT-6, and MCF as silicon sources. Porous β-SiC samples obtained from carbon–silica composites are characterized by high structural and sorption characteristics (S_BET up to 410 m2/g, V_pore up to 1.0 cm3/g). High hydrogen adsorption capacity of silicon carbide samples based on KIT-6 (up to 1.24 wt% at 77 K and 1 atm.), considering low adsorption energy (\( \left| {\Delta \mu_{0} } \right|_{{{\text{H}}_{2} }} \)) up to 2.3 kJ/mol for SiC vs. ca. 5.0 kJ/mol for carbon), was determined. The highest ever reported value among the existing porous materials was observed for specific adsorption of H₂ by SiC (specific adsorption on the pore surface, ρ up to 15 μmol/m2) corresponding to almost complete filling of the surface with hydrogen in the examined conditions (77 K, 1 atm.).