THE EFFECTS OF EXTERNAL CONDITIONS ON THE INTERNAL STRUCTURE OF CARBON AEROGELS

被引:46
作者
REYNOLDS, GAM
FUNG, AWP
WANG, ZH
DRESSELHAUS, MS
PEKALA, RW
机构
[1] MIT,DEPT ELECT ENGN & COMP SCI,CAMBRIDGE,MA 02139
[2] MIT,FRANCIS BITTER NATL MAGNET LAB,CAMBRIDGE,MA 02139
[3] LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550
关键词
D O I
10.1016/0022-3093(95)00029-1
中图分类号
TQ174 [陶瓷工业]; TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
Carbon aerogels with various particle (grain) sizes, mass densities and heat-treatment temperature were studied. Effects of these externally controllable parameters on the internal structure and properties of the carbon aerogel material were examined using techniques such as room-temperature Raman spectroscopy, temperature-dependent magnetic susceptibility and temperature-dependent dark- and photo-conductivities. The results show that the in-plane microcrystallite size increases with heat-treatment temperature, the electrical conductivity increases with mass density, and the particle size affects the unpaired spin disorder present, The transport mechanism common to all the samples is attributed to a variable-range hopping about a Coulomb gap.
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页码:27 / 33
页数:7
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