同步合成模板法制备热解炭及其电化学电容性能研究

研究制备新型炭材料是提高电化学电容器性能的有效途径。本文以二氧化硅干凝胶为模板,以合成间苯二酚-甲醛(RF)干凝胶为炭前驱体,采用同步合成模板法制得了比表面积达1100m²·g^-1,孔径分布集中,平均孔径为4.5nm的炭材料。循环伏安研究表明,与比表面积为1720m²·g^-1的活性炭相比,本研究制得的炭材料具有更优异的电化学电容性能,2mV·s^-1时比容量达195F·g^-1。

Study of Preparation and Electrochemical Capacitance Performance of Pyrolytic Carbon through Synchronously Synthetical Template Method

A new synchronously synthetical template method (SSTM) was brought forward to prepare carbon materials possessing controllable pore structure by mixing two sol-gel reactions, TEOS and resorcinol-formaldehyde in this paper. To testify the function of silica template to the formation of the pore structure of SSTM carbon, RF carbon by the pyrolysis of resorcinol-formaldehyde xerogel was also produced. N₂ sorption at 77K investigation showed that specific surface and average pore size of SSTM carbon were 1100m²·g^-1 and 4.5nm respectively, and its pore size distribution was very concentrative. The special structure of SSTM carbon was attributed to the simultaneous for-mation of template material (silica aquagel) and carbon precursor(resorcinol-formaldehyde aquagel). Voltage sweep cyclic voltametry was applied to investigate the electrochemical capacitance performance of SSTM carbon and T82 active carbon(1720m²·g^-1) parallel. SSTM carbon exhibited more excellent electrochemical capacitance perfor-mance, 195F·g^-1 at 2mV·s^-1, than that of T82 carbon, 150F·g^-1 at the same scan rate, although the specific surface of T82 carbon was much larger than that of SSTM carbon. Furthermore, the former exhibited better high current charge/discharge performance than the latter. Different characteristics of pore structures of the two carbons resulted in the difference of their electrochemical capacitance performance.