Tandem GCIB-ToF-SIMS and GCIB-XPS analyses of the 2-mercaptobenzothiazole on brass

Abstract

Surface analysis of 2-mercaptobenzothiazole (MBTH) adsorbed on brass from 3 wt.% NaCl solution was performed by means of X-ray photoelectron spectroscopy and tandem (MS/MS) time-of-flight secondary ion mass spectrometry (ToF-SIMS). These surface analytical techniques were used in association with the gas cluster ion beam (GCIB) sputtering method at various acceleration energies and cluster sizes, which slowly removes the surface layer and leaves the chemical information intact during the sputtering of the very thin surface layer. In addition, MS1 ToF-SIMS was used for 2D and 3D imaging to show the molecular and elemental distribution of the surface species. Using the tandem ToF-SIMS capability, the MS2 spectra clearly confirmed the presence of MBTH on the surface. Moreover, organometallic complexes were indicated, which formed between the MBTH and Cu ions released due to the corrosion of the brass. These analyses were performed based on the fragmentation products identified in the MS2 spectra.