Combined SIMS/TPD investigations of UHV-prepared tolyltriazole overlayers on Cu, Ni and Au

Abstract

The corrosion inhibitor tolyltriazole (TTA) has been investigated by combined secondary ion mass spectrometry (SIMS) and temperature programmed desorption mass spectrometry (TPD). TTA overlayers in the submonolayer to multilayer range are produced by in situ molecular beam exposure of Cu, Ni and Au substrates under UHV conditions. TPD yields information on different binding states and layer thickness. Molecular cluster ions as (2M−2H+Me) −, indicating the formation of TTA molecules in quasipolymeric chains, are emitted from all three substrates. Only for Cu we found a TTA desorption peak at high target temperatures (580 K), correlated to the emission of characteristic secondary ions, mainly (MH) − and (2M−2H+Cu) −. It is obviously the corresponding stable TTA monolayer on Cu that is responsible for the strong corrosion protection effect.