In Situ DRIFTS-MS Methanol Adsorption Study onto Supported NiSn Nanoparticles: Mechanistic Implications in Methanol Steam Reforming

Methanol adsorption over both supported NiSn Nps and analogous NiSn catalyst prepared by impregnation was studied by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to gain insights into the basis of hydrogen production from methanol steam reforming. Different intermediate species such as methoxides with different geometry (bridge and monodentate) and formate species were identified after methanol adsorption and thermal desorption. It is proposed that these species are the most involved in the methanol steam reforming reaction and the major presence of metal-support interface sites in supported NiSn Nps leads to higher production of hydrogen. On the basis of these results, a plausible reaction mechanism was elucidated through the correlation between the thermal stability of these species and the evolution of the effluent gas released. In addition, it was demonstrated that DME is a secondary product generated by condensation of methoxides over the acid sites of alumina support in an acid-catalyzed reaction.

UNDERSTANDING INSIGHT OF METHANOL ADSORPTION ON 2 ATOMIC COPPER DEPOSITED OVER ZNO(10¯1 0) SURFACE: A DFT STUDY

In this study, depositing with two copper atoms (2Cu) on ZnOsurface, obtaining 2Cu/ZnO surface model, and its applications then for adsorbed CH3OH were investigated using the density functional theory (DFT). In performances, 2Cu was adsorbed on ZnOsurface to form the model of 2Cu deposited over ZnO (2Cu/ZnO). Further, on 2Cu/ZnO surface model, the resulted analysis as density of state (DOS) and electron density difference (EDD) contour plot pointed out that two atomic Cu were formed by the transferred electrons from Cu to ZnO, leading Cu oxidation to become Cu+ ion, while was modeled 2Cu/ZnOsurface. To investigate CH3OH adsorption, many configurations of adsorbed CH3OH on the surface found, in which the most stable configurations were also identified. This result presented that methanol adsorption on 2Cu/ZnO is more favorable than that on ZnO in our previous works.