Preparation and hydrogen storage capacity of highly porous activated carbon materials derived from polythiophene

• Published in: International journal of hydrogen energy Vol. 36; no. 24; pp. 15658 - 15663
• Main Authors: Sevilla, M., Fuertes, A.B., Mokaya, R.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-12-2011; Elsevier
• Subjects: Activated carbon; Activation; Alternative fuels. Production and utilization; Applied sciences; Carbon; Energy; Exact sciences and technology; Fuels; Hydrogen; Hydrogen storage; Polythiophene; Porosity; Porous mateirals; Porous materials; Sulfur; Sulfur doping; Uptakes; Hydrogen storage; Porosity; Polythiophene; Sulfur doping; Hydrogen; Activation; Cryogenic temperature; Pore size; Storage capacity; Activated carbon; Preparation; Surface area; Sulfur
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2011.09.032

Highly porous carbons have been successfully synthesized by chemical activation of polythiophene with KOH. The activation process was performed under relatively mild activation conditions, i. e., a KOH/polymer weight ratio of 2 and reaction temperatures in the 600–850 °C range. The porous carbons thus obtained possess very large surface areas, up to 3000 m
2/g, and pore volumes of up to 1.75 cm
3/g. The pore size distribution of these carbons can be tuned via modification of the activation temperature. Thus, by increasing the activation temperature from 600 to 850 °C, the nature of the carbons changes gradually from microporous to micro-mesoporous (with small mesopores of up to 2.5 nm). The polythiophene-derived activated carbons are sulfur-doped with sulfur contents in the 3–12 wt% range. The sulfur content decreases at higher activation temperature. The hydrogen storage capacity of these activated carbons, at cryogenic temperature and 20 bar, is up to 5.71 wt% with an estimated maximum hydrogen uptake of 6.64 wt%. Their ease of preparation and high uptake makes the polythiophene-derived carbons attractive hydrogen storage materials.