| 초록 |
Using DFT calculations, we studied the dehydrogenation process of perhydro-dibenzyltoluene (H18-DBT) on Pt1/3/M and Pt2/3/M surface alloys (M = Fe, Ni, and Cu). For Pt1/3/M, Pt/Ni(111) was revealed to have the highest performance for dehydrogenation of H18-DBT, while Pt/Cu(111) was found to require the highest energy for dehydrogenation. The rank for the performance of releasing hydrogen was found to be as Pt/Fe(100) > Pt/Ni(111) > Pt/Cu(111) in Pt2/3/M alloys, demonstrating the effect of Pt surface concentration on the dehydrogenation performance of these catalysts. This is attributed to the shift of the d-band centers upon the change of Pt surface concentration. Thus, Pt2/3/Fe(100) can be proposed to be the promising surface alloy catalyst among the other catalysts. The RDS of the dehydrogenation was found to be identical as the 1st dehydrogenation stage from the ring in the middle regardless of the Pt surface concentration. In addition, the reaction energy of the step were correlated with the adsorption strength of hydrogen on the catalysts, revealing that the hydrogen adsorption energy is a useful descriptor for effectively predicting the catalytic activity for dehydrogenation. |
