Thermal reactions of mercaptoethanol on Cu(1 0 0)

Abstract

Reflection-absorption infrared spectroscopy (RAIRS) and temperature-programmed reaction/desorption (TPR/D) have been employed to investigate the thermal decomposition of HSCH 2CH 2OH on Cu(1 0 0) and the surface intermediates involved. The surface reactions of HSCH 2CH 2OH proceed via several stages in sequence, including production of surface intermediates of –SCH 2CH 2OH, –SCH 2CH 2O–, and the species possibly containing >C C O or >C C S. Carbon-containing products of CH 4, C 2H 4, and CH 3CHO evolve between 300 and 500 K and C 2H 4 is the major product. Desorption of sulfur-containing products is not observed. HSCH 2CH 2OH dissociates on Cu(1 0 0) and oxygen-precovered Cu(1 0 0) to form –SCH 2CH 2OH at dosing temperature of 115 K. However –SCH 2CH 2O– and the species containing >C C O or >C C S are generated at lower temperatures on oxygen-precovered Cu(1 0 0). C 2H 4 is also the major desorption product from HSCH 2CH 2OH on oxygen-precovered Cu(1 0 0).