Catalytic Aspects of Pt/Pd Supported on ZnO Rods for Hydrogen Production in Methanol Steam Reforming

Abstract

We present a combined experimental and theoretical study for catalytic performance of Pt/Pd supported on ZnO rods for methanol steam reforming reaction (MSR) for hydrogen production. The samples were extensively characterized by Adsorption– Desorption of N2 (BET), electron microscopy in scanning and transmission mode (SEM/TEM), X-ray diffraction (XRD), temperature programed reduction (TPR), and mass spectroscopy (MS). Results, showed typical diffraction peaks corresponding to hexagonal Zincite structure and tetragonal PtZn, PdZn and PtPdZn alloys which were identified by XRD, HRTEM and the last structure by modeling simulation. The crystallographic characterization after catalytic testing indicates that intermetallic PtZn phase on Pt/ZnO sample was more stable in comparison to PdZn on Pd/ZnO catalyst. In addition, Pt stabilize the PdZn structure in the bimetallic catalyst. The catalytic reactivity measured from 200 to 450 °C, indicates that Pt/ZnO-rod sample possess superior catalytic activity from the series as completed on this study. The methanol conversion was tracked by mass spectroscopy concluding minimal changes in outlet signals which suggests samples are chemically stable throughout the complete catalytic reaction. Furthermore, the computer assisted density of states calculations indicate that electron donation from platinum into the zinc oxide support might be the explanation for better catalytic performance.