摘要
在110℃～170℃范围内对糠醛-酚醛基有机气凝胶进行氧化处理1h～7h,考察了氧化对有机气凝胶热裂解产生的炭气凝胶孔结构的影响。结果表明:氧化可避免有机气凝胶纳米骨架在裂解过程中的塑性阶段发生,有机气凝胶的适度氧化有利于纳米结构的稳定化;由于空气在大、中、微孔中扩散的差别,氧化前处理对炭气凝胶的大、中、微孔有不同的影响,尤其对接近中孔的大孔影响最大。在所考察的氧化温度和时间内,130℃/7h时或150℃/3h时的适度氧化条件下,可显著提高中孔孔容、中孔比表面和BET比表面。
Organic aerogels, prepared by sol-gel polymerization of phenolic and furfural, were oxidized at 110 to 170 ℃ for 1 to 7h in air. The effect of oxidation temperature and time on the pore structure of the carbon aerogels was investigated. It is found that oxidation under appropriate conditions can stabilize a nano-network of organic aerogels during pyrolysis by preventing plasticity. However, the oxidative effect on micro-, meso- and macro-pores is quite different. A mild condition is appropriate for macro-pores while a severe condition is needed for meso- and micro-pores due to a faster diffusion of air into macro-pores than into meso- and micro-pores. The appropriate oxidation parameters for an improved mesopore volume and surface area are 130 ℃ for 7 h or 150 ℃ for 3 h in air.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2008年第4期309-313,共5页
New Carbon Materials
基金
国家自然科学基金(50872033)
国家科技支撑计划项目(2007BAE55B03)
973项目(2006CB600907)资助~~
关键词
有机气凝胶
炭气凝胶
氧化处理
孔结构
Organic aerogels, Carbon aerogels, Oxidation
Pore structures.
