Thermal Chemistry of Thiazole on Cu(100) and O/Cu(100) Surfaces

Abstract

Temperature-programmed reaction/desorption (TPR/D) X-ray photoelectron spectroscopy (XPS) and reflection-absorption infrared spectroscopy (RAIRS) with the aid of density-functional-theory calculations to analyze the adsorption and thermal chemistry of thiazole on Cu(100) and oxygen-precovered Cu(100) At 120 K thiazole is predominantly adsorbed on Cu(100) via N-Cu interaction and with the aromatic ring perpendicular to the surface At 200 K the ring begins to rupture and forms a small amount of sulfur atoms (S(ad)) on the surface As the temperature further increases C2H2(~290 K) H2(~597 737 K) and HCN(~525 K ~610 K ~737 K) evolve as the reaction products -SCHNCHCH- -SCHCHNCH- and/or -CHNCHCH- are proposed to be the surface intermediates formed in the thiazole reaction on Cu(100) The adsorption of thiazole on O/Cu(100) at 120 K is similar to case of Cu(100) In the presence of oxygen atoms on Cu(100) thiazole also reacts on the surface and eventually generates S(ad) but the product distribution is different from that of Cu(100) with evolution of H2(~388 K ~604 K) H2O (~438 K) C2H2 (279 K) CO (~373 K 604 K) CO2 (~373 K ~604 K) and N2 (~834 K) In addition to the three reaction intermediates proposed in the case of Cu(100) >C=C=O NCO and another surface intermediate with C-O group are possibly formed in the thiazole reaction on O/Cu(100)

Date of Award	2019
Original language	English
Supervisor	Jong-Liang Lin (Supervisor)