Polymer-infiltrated SiO2 inverse opal photonic crystals for colorimetrically selective detection of xylene vapors

In this study, we report the development of a polymer infiltrated SiO2 inverse opal photonic crystal (IOPC) for selective detection of xylene vapors. Poly(4-vinylbenzyl chloride-co-methyl methacrylate) (P(VBC-co-MMA)), which shows strong affinity towards xylenes because of their similar solubility parameters, was synthesized and infiltrated into SiO2 IOPC (P(VBC-co-MMA)-SiO2 IOPC). The resulting P(VBC-co-MMA)-SiO2 IOPC sensor shows color change from green to red upon exposure to xylene vapors as the diffusion and adsorption of gaseous xylenes increased the effective refractive index of the IOPC. It shows good sensitivity with a limit of detection of 0.51, 0.41 and 0.17 μg mL−1 for o-xylene, m-xylene, and p-xylene, respectively. The sensor also shows excellent selectivity for xylenes over other organic vapors. In addition, the P(VBC-co-MMA)-SiO2 IOPC sensor demonstrates quick response and good reversibility. This polymer infiltrated IOPC sensor provides a universal strategy for the detection of organic vapors through building a sensor using polymers with similar solubility parameters to targeting vapors.Graphical abstract
Source: Sensors and Actuators B: Chemical - Category: Chemistry Source Type: research