Sol-gel based phenolphthalein encapsulated heterogeneous silica-titania optochemical pH nanosensor

Abstract

Thermally stable phenolphthalein encapsulated silica-titania nanomatrix is fabricated by sol-gel method for optochemical pH sensing. The particle size ~56-121 nm is obtained with average surface roughness of 3.95 nm after the encapsulation of dye which is highly appropriate for optical and sensing applications. High surface area value ~218 m2/g, pore volume of 0.16 cm3/g and pore diameter of 31.49 Å is obtained after encapsulation. Furthermore, the sensor response is optimized at pH 10 Fast response time 1-2s, sensitivity with good reproducibility identify that the fabricated optochemical nanosensor is challenging for the detection of pH at room temperature