Author/Authors :
Chen، نويسنده , , Chien-Hung and Chung، نويسنده , , Tsui-Yun and Shen، نويسنده , , Chin-Chang and Yu، نويسنده , , Ming-Sheng and Tsao، نويسنده , , Cheng-Si and Shi، نويسنده , , Gia-Nan and Huang، نويسنده , , Chen-Chia and Ger، نويسنده , , Ming-Der and Lee، نويسنده , , Wen-Lung، نويسنده ,
Abstract :
In this study a two-dimensional graphene sheet (GS) doped with palladium (Pd) nanoparticles was physically mixed with a superactivated carbon (AC) receptor and used as a hydrogen adsorbent. The hydrogen adsorption/desorption isotherm of the Pd-doped GS catalyst/AC composite (Pd-GS/AC) is determined using a static volumetric measurement at room temperature (RT) and pressure up to 8 MPa. The experiments show that the H2 uptake capacity of 0.82wt.% for Pd-GS/AC is obviously enhanced, measuring 49% more than the 0.55wt.% for Pd-free GS/AC at RT and 8 MPa. Highly reversible behavior of Pd-GS/AC is also observed. Moreover, the isosteric heat of adsorption for Pd-GS/AC (−14 to −10 kJ/mol) is higher than that for pristine AC (−8 kJ/mol). An increase in H2 uptake in the Pd-GS/AC suggests the occurrence of a relatively strong interaction between the spilt-over H and the receptor sites due to the spillover effect.
