Fabrication, characterization, and malaria biomarker VOC-sensing properties of WO3-doped polyaniline

The polyaniline-WO3 nanocomposite with 15% doping concentration is synthesized using in situ chemical polymerization. Structural and morphological characterizations were done using XRD, FESEM, HR-TEM, and FTIR. The bandgap energy of the synthesized nanocomposite with different doping concentrations of WO3 was calculated using UV–Visible absorption spectra. Dielectric studies confirmed the non-Debye nature of the material. The synthesized polymer nanocomposite was used for making a spin-coated VOC sensor for the detection of 3-Carene and α-Pinene, the biomarker volatile organic compounds (VOCs) of malaria. The sensing layer was prepared by mixing polyaniline-WO3 nanocomposite with Polyvinylidene fluoride (PVDF) using N-Methyl-2-pyrrolidone (NMP). The effect of VOCs at concentrations of 1.5 ppm, 3 ppm, and 4.5 ppm on the electrical resistance of the polymer nanocomposite films at room temperature during sensing characteristics was studied. The sensitivity and response time of the sensors with Taconic substrate were studied and by using the sensor an IoT-based portable device was developed. Sensing results confirmed that the polyaniline-WO3 nanocomposite is suitable for making malaria biomarker VOC sensor.