Effect of pore structure of activated carbon fibers on hydrogen adsorption

Abstract

The activated carbon fibers were air-oxidized and their textural properties were well characterized by N2 and CO2 adsorption. The correlation of pore size distribution of raw and treated activated carbon fibers with hydrogen adsorption performance indicated that ultramicropores dominate the hydrogen adsorption at low pressure. However, hydrogen molecules are not only trapped in the ultramicropores, but also adsorbed in the supermicropores at 77 K and high pressure. The narrow ultramicropores represent the higher energy adsorption sites that can adsorb gas molecules at high temperature and very low pressure. CO2 adsorption is proven to be necessary to provide complementary characterization of narrowest pores.