Hydrogen Storage Using Platinum-Supported Ceria Dispersed on Activated Carbon

Abstract

In the current work, carbon materials were used in the hydrogen adsorption process, specifically as carbons doped with platinum dispersed on ceria. The textural characterization results of the prepared samples and the starting carbon showed the presence of both micro- and mesopores. On the other hand, it has been observed that the specific areas were inversely proportional to the CeO₂ loading. In addition, the amount of adsorbed hydrogen increased after doping the carbon with platinum and, even more, when the carbon was doped with Pt dispersed on ceria (2.2 mg/g at 25°C and 30 bar). However, there was a ceria optimum from which the adsorption capacity decreased (10% wt). The results of temperature-programmed desorption (TPD) of hydrogen indicated a high affinity between Pt and H₂ that enhanced H₂ adsorption process by establishing chemical bonds between the metal particles and H₂. Precisely, the presence of metallic Pt particles dispersed on ceria considerably promotes the spillover process of hydrogen on carbon. This can be confirmed by hydrogen adsorption–desorption isotherms, that showed that complete desorption of chemisorbed hydrogen required an increase of temperature.