Self assembly of 16-mercapto-1-hexadecanol on gold: surface characterization and kinetics

The chemical composition, film structure and surface wetting properties at different self-assembly formation stages for 16-mercapto-1-hexadecanol on g old were investigated in this work. Complementary surface analytical techni ques (ESCA, infrared reflection absorption spectroscopy (IRAS), time-of-fli ght secondary ion mass spectrometry (TOF-SIMS), and contact angle measureme nts) explored the progression of self-assembly at a molecular level from di fferent perspectives. At the earlier stages during the formation of a self- assembled monolayer, molecules adsorbed onto the gold surface in a manner s uggesting island growth. This was followed by a slower process where the mo nolayer underwent a phase transition by conformational reconstruction and r ealignment of molecular axes with the surface normal. The contact angle beh avior can be related to surface coverage as well as molecular orientation. In integrating spectroscopic, thermodynamic and kinetic data, a clearer pic ture was obtained about mechanistic and structural aspects of self-assemble d molecular thin films. (C) 1999 Elsevier Science S.A. All rights reserved.