Tetramethyl ammonium as masking agent for molecular stencil patterning in the confined space of the nano-channels of 2D hexagonal-templated porous silicas.
The molecular stencil patterning (MSP) technique is a new surface molecular engineering technique developed for cation-templated porous silicas to graft several functions with vicinity control. First, tetramethylammonium ions (TMA(+)) are introduced by ion exchange of the cetyltrimethyl-ammonium template (CTA(+)). Then, the coverage is controlled to create a masking array of cations, the pattern of which is produced by mutual electrostatic repulsion. A first function is grafted, here monopodal trimethylsilyl groups (TMS) or dipodal ethyl-1,2-bis(dimethylsilyl) (EBDMS) groups. After the removal of the masking cations, a second function is grafted using here N-(2-aminoethyl)-3-amino-propyltrimethoxysilane precursor. The distribution of N-(2-aminoethyl)-3-amino-propylsilyl functions (AAPS) is probed by complexation to Cu(ii) ions. X-Ray diffraction, N(2) adsorption-desorption isotherms, (13)C solid-state NMR, IR, UV-visible and electron paramagnetic resonance (EPR) techniques show that MSP can produce isolation of AAPS by TMS, or even better by EBDMS groups, with preservation of the silica pore structure.
Zhang
Kun
K
Laboratoire de Chimie, Ecole Normale Supérieure de Lyon, Institut de Chimie de Lyon, Université de Lyon, 46 Allée d'Italie, 69364 Lyon cedex 07, France.
Albela
Belén
B
He
Ming-Yuan
MY
Wang
Yimeng
Y
Bonneviot
Laurent
L