On the importance of purity for the formation of self-assembled monolayers from thiocyanates.
Assembly of dodecyl thiocyanate (C12SCN) from ethanol solution onto Au(111)/mica substrates was investigated by scanning tunneling microscopy (STM), near edge X-ray absorption fine structure spectroscopy (NEXAFS), X-ray photoelectron spectroscopy (XPS), and infrared reflection-absorption spectroscopy (IRRAS). Contrary to previous reports, thiolate monolayers formed by cleavage of the S-CN bond can be obtained whose quality is at least as good as that of self-assembled monolayers (SAMs) formed directly from the thiol analogue of C12SCN, dodecanethiol (C12SH). However, the achievable quality is strikingly dependent on the purity of the thiocyanate with even low levels of contamination impeding the formation of structurally well-defined monolayers.
Shen
Cai
C
EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews KY16 9ST, United Kingdom.
Buck
Manfred
M
Wilton-Ely
James D E T
JD
Weidner
Tobias
T
Zharnikov
Michael
M
D016252:Microscopy, Scanning Tunneling; D013053:Spectrophotometry; D013861:Thiocyanates / Q000737:chemistry*
D013861:Thiocyanates; C031760:thiocyanate