This study investigates the performances of hydrogen adsorption on activated carbon separated by TiO2 nanoparticles with the presence of an electric potential. Four species with different TiO2 contents were prepared. Hydrogen adsorption measurements on those TiO2-coated materials, with or without an external electric field, were made, respectively. The results showed that the adsorption capacity could be enhanced by introducing the electric potential and the enhancement increased with increasing amount of TiO2 nanoparticles. The hydrogen adsorption capacity on TiO2 particles is negligible, and thus there is no increase in hydrogen adsorption on TiO2 particles alone when an electric field is applied. The effect of the dielectric coating is demonstrated. (C) 2013 Elsevier B.V. All rights reserved.