Mesoporous structure of carbon fibers and carbon nanospheres were successfully prepared from combination of sol-gel method and electrospinning techniques. Mesoporous carbon with controllable pore size can be formed via the pyrolysis of resorcinol/formaldehyde (RF) gel. The RF gel was prepared by the sol-gel polycondensation of resorcinol (R) and formaldehyde (F) with sodium carbonate (C) as basic catalyst. Morphology and size distribution of RF fibers and RF particles can be controlled by aging condition, aging time of RF gel, preparation condition for RF gel and the processing parameters. Products from electrospinning of RF gel prepared by different condition and aged in 8% RH environment are micro-fibers with the average fiber diameter in the range of 1-5 µm. For the RF-gel aged under high humidity (e.g. 45%, 75% and 100% RH), the products were found to be mostly spherical particles deposited on the collector. Addition of aluminium precursor, i.e., aluminium acetylacetonate into the RF gel followed by electrospinning of the gel were also investigated.

Thesis (M.Eng.)--Chulalongkorn University, 2010