Carbon aerogel/carboxylated carbon nanotubes: porous structure and electrical conductivity properties

Abstract

The aim of this study is to investigate the effect of various weight percentages of multi-walled-carbon nanotubes (CNT) with carboxyl groups on the properties of carbon aerogels (CA). The electrical conductivity, shrinkage and morphology of carbon aerogel- functionalized carboxylated carbon nanotubes composites (COO-CNT sample) were characterized and compared with carbon aerogel composites synthesized by CNT dispersed by sodium dodecyl sulfate (SDS-CNT sample) and carbon aerogel composites with raw CNT (R-CNT sample). According to the obtained results, the shrinkage of R-CNT sample does not noticeably change with increasing CNT weight percentages (wt%), while the decreased significant shrinkage of COO-CNT and SDS-CNT samples might be due to better dispersion of CNT. In addition, while the electrical conductivity of R-CNT is maintained at the same level, it is enhanced by increasing the CNT wt% for COO-CNT and SDS-CNT samples which could be attributed to the pathways with higher conductivity in their matrix. Moreover, the higher mechanical strength (lower shrinkage) of SDS-CNT sample compared to COO-CNT sample can be ascribed to a more uniform arrangement of CNT inner network, as observed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM).