Facile synthesis of ternary polypyrrole/Prussian blue/Titanium dioxide composite and their performance for isopropyl alcohol sensing at room temperature

Polypyrrole/Prussian blue/Titanium dioxide composite, (PPy/PB/TiO₂) was successfully prepared through polymerization of pyrrole and formation of PB nanocubes and TiO₂ nanoparticles. Synthesized composite were characterized structurally and morphologically through XRD and FESEM analysis. XRD pattern revealed the crystallinity of the polymer composite which suggests a strong interaction between PPy, PB and anatase phase of TiO₂ nanoparticles. The morphology of the composite shows the irregular spherical particles of PPy, PB and TiO₂ with aggregates. PPy/PB/TiO₂ coated intensity modulated fiber optic sensor for the detection of isopropyl alcohol at room temperature is reported. The synthesized polymer composite is coated on clad removed polymethyl methacrylate (PMMA) fiber by dip coating technique and PPy/PB/TiO₂ coated fibers are used as sensors. The sensor response is studied by measuring the change in output light intensity for different isopropyl alcohol concentrations in the range of 0-500 ppm. The sensor exhibited a linear variation in the output light intensity with the toxic vapor concentration. Further, the gas sensitivity of the sensor is discussed briefly.