Optical fibre based acetone sensor using Pd modified WO3 nanostructures

Acetone is one of the biomarkers required for breathe analysis. Herein, we report, an optical acetone detector based on Pd decorated WO3 nanostructures ([email protected]3). The gas sensitive [email protected]3 is being coated on clad removed fiber optic cable in which refractive index changes after exposure to gases. A fiber optical core made from PMMA is used for detection of light absorbed through the fiber optical cable for different gases such as ammonia, benzene, acetone, NOx, ethanol, methanol, TEA, TMA, toluene and formaldehyde. A thickness dependent study of coating material has been carried out for detection of analyte gas/vapor. Among all tested gases, acetone showed the maximum response with optimized [email protected]3 coating thickness at 10 µm. Both WO3 and [email protected]3 showed the response towards test gases but this response was found to be increased for [email protected]3. Acetone response was studied for lower (20–100 ppm) and higher (100–1000 ppm) gas concentrations at room temperature. Absorption of acetone was found to be increased after increasing the gas concentration. The gas sensing characteristics and sensing mechanism is also discussed in detail.