Impact of CeO2 doped ZnO binary metal oxide nanocomposites as clad modified fiber optic VOC gas sensor for exhaled breath analysis

Abstract

The detection of volatile organic compounds (VOCs) in ambient environments has opened up a new field for the quick, risk-free, and potentially low-cost identification of respiratory illnesses. In this context, CeO2 doped ZnO nanocomposites were produced through the sol-gel technique at various ratios (CeO2:ZnO at 1:4, 4:4, and 4:1, respectively), and their gas sensing capability was evaluated and shown using a clad modified fiber optic sensor to study its potential as a VOC detector. The study was based on the concepts of evanescent wave absorption. The modified cladded optical fiber was exposed to the ammonia, ethanol, and methanol gas medium in the testing laboratory. At room/chamber temperatures, the sensor's sensitivity is tested, and was observed that CeO2 doped ZnO at 4:1 ratio exhibited better sensitivity towards ammonia gas vapour.