Resolving the Chemical Nature of Nanodesigned Silica Surface Obtained via a Bottom-up Approach

Abstract

The covalent grafting on silica surfaces of a functional dendritic organosilane coupling agent inserted, in a long alkyl chain monolayer, is described. In this paper, we show that depending on experimental parameters, particularly the solvent, it is possible to obtain a nanodesigned surface via a bottom-up approach. Thus, we succeed in the formation of both homogeneous dense monolayer and a heterogeneous dense monolayer, the latter being characterized by a nanosized volcano-type pattern (4-6 nm of height, 100 nm of width, and around 3 volcanos/μm(2)) randomly distributed over the surface. The dendritic attribute of the grafted silylated coupling agent affords enough anchoring sites to immobilize covalently functional gold nanoparticles (GNPs), coated with amino PEG polymer to resolve the chemical nature of the surfaces and especially the volcano type nanopattern structures of the heterogeneous monolayer. Thus, the versatile surface chemistry developed herein is particularly challenging as the nanodesign is straightforward achieved in a bottom-up approach without any specific lithography device.

Self-assembled monolayer for AFM measurements of Tobacco Mosaic Virus (TMV) at the atomic level

“…The successful chemical reaction was analysed by PM-IRRAS revealing the complete disappearance of the nitro band (n as NO 2 ¼ 1529 cm À1 ) and the appearance of a new broad band around 1707 cm À1 characteristic of acid groups as previously reported. 18 For SAM-NO 2 and SAM-COOH the methylene stretching bands are observed in similar positions at 2927 and 2855 cm À1 respectively for the antisymmetric (n as (CH 2 )) and symmetric (n s (CH 2 )) modes. The high wavenumbers of these modes indicates that the alkyl chains were disordered in the graed molecules whereas similar intensities do not reveal any degradation of the monolayer during the photochemical cleavage.…”

Mixed Self‐Assembled Monolayers with Internal Urea Group on Silica Surface

“…The control of composition and topography of mixed SAMs is dependent on parameters such as the structure of the silane compounds and the deposition conditions. Recently, we have shown the formation of both homogeneous and heterogeneous dense monolayers depending on the nature of the solvent . The latter was characterized by nanodomains (5 nm height, 100 nm width) randomly distributed over the surface.…”

“…Recently, we have shown the formation of both homogeneous and heterogeneous dense monolayers depending on the nature of the solvent. [19] The latter was characterized by 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 nanodomains (5 nm height, 100 nm width) randomly distributed over the surface. Several studies showed that the preparation of mixed SAMs with a solution composed of trichlorosilane and tri-or mono-alkoxysilane was complicated by the coadsorption method due to the difference of reactivity of the two compounds which could not be balanced by the deposition solution composition.…”

Design of PAMAM-COO dendron-grafted surfaces to promote Pb(ii) ion adsorption

“…5 Silica gel is one such adsorbent whose effectiveness is dependent on the functional groups covalently bonded to the surface. [6][7][8][9] Starburst polyamidoamine (PAMAM) dendrimers have demonstrated binding affinities for metal ions. 1,10 By tethering dendrimers to the solid support, promising novel adsorbents can possess the mechanical and thermal stability of the support, and the strong affinity and high loading capacities of dendrimers.…”