Exhaled breath gas sensing using pristine and functionalized WO3 nanowire sensors enhanced by UV-light irradiation

• Published in: Sensors and actuators. B, Chemical Vol. 273; pp. 1719 - 1729
• Main Authors: Saidi, Tarik, Palmowski, Dariusz, Babicz-Kiewlicz, Sylwia, Welearegay, Tesfalem Geremariam, El Bari, Nezha, Ionescu, Radu, Smulko, Janusz, Bouchikhi, Benachir
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 10.11.2018
• Subjects: Exhaled breath analysis; Metal nanoparticles; Operating temperatures; Sensor response enhancement; UV-light irradiation; WO3nanowire sensors; WOnanowire sensors; Metal nanoparticles; WO3nanowire sensors; Exhaled breath analysis; Sensor response enhancement; Operating temperatures; UV-light irradiation
• ISSN: 0925-4005; 1873-3077; 1873-3077
• DOI: 10.1016/j.snb.2018.07.098

•AACVD was carried out to produce pristine and differently functionalised WO3.•The grown sensors were characterised with AFM, SEM, TEM and EDX-ray.•UV-light irradiation enhanced the sensors’ responses towards breath exposure.•The most sensitive sensor for breath was the Au-doped WO3 and operating at 160 °C. The development of advanced metal-oxide-semiconductor sensing technologies for the detection of Volatile Organic Compounds (VOCs) present in exhaled breath is of great importance for non-invasive, cheap and fast medical diagnostics. Our experimental studies investigate the effects of operating temperature selection and UV-light irradiation on improving the response of WO3 nanowire sensors towards exhaled breath exposure. Herein, six WO3 nanowire sensors (both pristine and doped with a range of metal nanoparticles such as Pt, Au, Au/Pt, Ni and Fe) were synthesised via Aerosol-Assisted Chemical Vapour Deposition (AACVD) and characterized by means of Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray (EDX-ray). Breath measurements were performed in the dark and under UV-light irradiation at various sensor operating temperatures. The results demonstrate that UV-light irradiation combined with the optimisation of the sensors’ operating temperature can greatly enhance the sensors’ responses towards breath exposure.