Synthesis of Vertically Aligned Porous Silica Thin Films Functionalized by Silver Ions

Andrii Fedorchuk,Magdalena Laskowska,Krzysztof Cpałka,Łukasz Laskowski,Alain Walcarius,Neus Vila,Paweł Kowalczyk

doi:10.3390/ijms22147505

Abstract

In this work, we have developed a chemical procedure enabling the preparation of highly ordered and vertically aligned mesoporous silica films containing selected contents of silver ions bonded inside the mesopore channels via anchoring propyl-carboxyl units. The procedure involves the electrochemically assisted self-assembly co-condensation of tetraethoxysilane and (3-cyanopropyl)triethoxysilane in the presence of cetyltrimethylammonium bromide as a surfactant, the subsequent hydrolysis of cyano groups into carboxylate ones, followed by their complexation with silver ions. The output materials have been electrochemically characterized with regard to the synthesis effectiveness in order to confirm and quantify the presence of the silver ions in the material. The mesostructure has been observed by transmission electron microscopy. We have pointed out that it is possible to finely tune the functionalization level by controlling the co-condensation procedure, notably the concentration of (3-cyanopropyl)triethoxysilane in the synthesis medium.

Highlights

Mesoporous silica thin films built of silicon dioxide have an extraordinary developed surface due to the presence of a vast amount of pores in the structure [1], usually ordered [2]
An efficient way to prepare them is the electro-assisted self-assembly method (EASA), resulting in uniform thin films made of vertically aligned mesopore channels, ordered in a 2D hexagonal pattern, with a pore diameter of about 2 nm and wall thickness of 1 nm [23,24]
The real potential of porous silica thin films became clear after taking into account the possibility of their functionalization [4,25,26,27,28]

Summary

Introduction

Mesoporous silica thin films built of silicon dioxide (mainly amorphous) have an extraordinary developed surface due to the presence of a vast amount of pores in the structure [1], usually ordered [2]. 20 nm Despite their extraordinary structure, the real potential of porous silica thin films became clear after taking into account the possibility of their functionalization [4,25,26,27,28] From this point of view vertically aligned mesoporous silica layer can be treated as a unique template that can be precisely modified for particular needs via the deposition of corresponding units We are capable of finely tuning their number, realizing by it the idea of the “2D solid solvent” [41]

Methods

Results

Conclusion