Paper HC-ThP7
Intermolecular Interactions of Small Alcohols on Au(111)

Thursday, October 24, 2019, 6:30 pm, Room Union Station B

Metal oxide nanoparticles supported on Au(111) are active catalysts for the oxidation of small alcohols to form industrially significant products and intermediates such as aldehydes. In a systematic study to better understand the adsorption behavior of these small alcohols, coverage studies of methanol, ethanol, and 1-propanol have been conducted on Au(111) using ultrahigh vacuum temperature-programmed desorption (TPD). These three alcohols molecularly adsorb to distinct terrace, step edge, kink, and multilayer sites, for which desorption energies are calculated by Redhead’s peak maximum method. The use of complete analysis as a more accurate method for the calculation of desorption energies is also explored for the case of methanol. TPD experiments and subsequent analysis uniquely allow for the investigation of both adsorbate-surface interactions and adsorbate-adsorbate intermolecular interactions. This provides a more robust understanding of surface phenomena and affords valuable data for modelling and predicting the adsorption behavior of small alcohols on Au(111)-based catalysts. It is shown that, for all adsorption sites, desorption energy is directly proportional to carbon chain length. However, the rate at which desorption energy increases varies distinctly between adsorption sites. This study indicates that the role of intermolecular interactions in the adsorption behavior of small alcohols varies between adsorption sites, and can be predicted for other small alcohols.