Adsorption of silanes bearing nitrogenated lewis bases on SiO2/Si (100) model surfaces

• Published in: Journal of colloid and interface science Vol. 286; no. 1; pp. 303 - 309
• Main Authors: SALVADOR ANDRESA, Juliana, MACHADO REIS, Rafael, PEREZ GONZALEZ, Eduardo, SILVA SANTOS, Leonardo, NOGUEIRA EBERLIN, Marcos, DE PAULA NASCENTE, Pedro Augusto, TOMIE TANIMOTO, Sonia, SPINOLA MACHADO, Sérgio Antonio, RODRIGUES-FILHO, Ubirajara P
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier 01-06-2005
• Subjects: Chemistry; Exact sciences and technology; General and physical chemistry; Surface physical chemistry; Self assembly; Atomic force microscopy; Nitrogen heterocycle; 3-Imidazolylpropyltrimethoxysilane; AFM; X ray; Silica; Silicon dioxide; Thin film; MALDI-TOF MS; Self-assembled thin films; Pyridine; Adsorption; Six membered ring; Silicon wafer; Photoelectron spectrometry; 4-(N-Propyltriethoxysilane-imino)pyridine; Models; Silicon; XPS; Wafer; Silane
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2005.01.019

The present paper describes the one-pot procedure for the formation of self-assembled thin films of two silanes on the model oxidized silicon wafer, SiO2/Si. SiO2/Si is a model system for other surfaces, such as glass, quartz, aerosol, and silica gel. MALDI-TOF MS with and without a matrix, XPS, and AFM have confirmed the formation of self-assembled thin films of both 3-imidazolylpropyltrimethoxysilane (3-IPTS) and 4-(N-propyltriethoxysilane-imino)pyridine (4-PTSIP) on the SiO2/Si surface after 30 min. Longer adsorption times lead to the deposition of nonreacted 3-IPTS precursors and the formation of agglomerates on the 3-IPTS monolayer. The formation of 4-PTSIP self-assembled layers on SiO2/Si is also demonstrated. The present results for the flat SiO2/Si surface can lead to a better understanding of the formation of a stationary phase for affinity chromatography as well as transition-metal-supported catalysts on silica and their relationship with surface roughness and ordering. The 3-IPTS and 4-PTSIP modified SiO2/Si wafers can also be envisaged as possible built-on-silicon thin-layer chromatography (TLC) extraction devices for metal determination or N-heterocycle analytes, such as histidine and histamine, with "on-spot" MALDI-TOF MS detection.