Structural and optical properties of surfactant assisted SiO2-TiO2 hybrid matrix for pH sensing: Sol-gel approach

Abstract

Structural and optical properties of surfactant-assisted SiO2-TiO2 hybrid matrix as a highly responsive optical sensing material by sol-gel method are investigated. Microscopic results indicate the uniform morphology with large pores without any cracks. Matrices have a high surface area (489–342 m2/g), which has more capability to sense the broader pH range. From UV–visible spectroscopy, it is found that after encapsulation, matrix has ~ 78 % optical transparency with low refractive index of 1.44 corresponding to thickness 138.7 nm. Sensing analysis revealed that the prepared coating has good sensitivity at pH 12 and fast response time. Low refractive index and highly porous matrix, combined for achieving a good responsive optical chemical sensors. This research also opens an aveanue for ths material to be considered as a functional coating.