Characterization of PLD grown WO 3 thin films for gas sensing

Abstract

Tungsten trioxide (WO 3 ) thin films were grown by pulsed laser deposition (PLD) with the aim to be applied in gas sensors. The films were studied by atomic force microscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and profilometry. To study the gas sensing behavior of these WO 3 films, they were deposited on quartz resonators and the quartz crystal microbalance (QCM) method was applied to analyze their gas sensitivity. Synthesis of tetragonal-WO 3 films starting from a target with predominantly monoclinic WO 3 phase was observed. The films deposited at 300 °C presented a surface topology favorable for the sorption properties, consisting of a film matrix with protruding craters/cavities. QCM prototype sensors with such films were tested for NO 2 sensing. The PLD grown WO 3 thin films show good sensitivity and fast reaction at -3/20 -room temperature, even in as-deposited state. With the presented technology, the manufacturing of QCM gas sensors is simple, fast and cost-effective, and it is also suitable for energy-effective portable equipment for on-line monitoring of environmental changes.

Pulsed Laser Deposited Films for Microbatteries

“…Highly transparent WO 3 films exhibiting strong coloration and fast and full bleaching were prepared under PLD conditions (Φ = 1 J·cm −2 , T s = 250 • C, P O 2 = 16 Pa, and d = 40 mm) [252]. WO 3 films were also prepared using similar PLD parameters for applications in gas sensors [253][254][255].…”

Graphene-Modified ZnO Nanostructures for Low-Temperature NO2 Sensing

“…11−13 For detecting NO 2 , a number of gas sensors based on semiconductors have been developed (see Table S1, Supporting Information). 14,15 Because of the chemical stability and low cost, NO 2 sensors based on metal oxides, such as ZnO, 16−18 SnO 2 , 19−21 WO 3 , 22−24 Fe 2 O 3 , 25,26 and NiO, 27,28 have widely been reported. Because of the high operating temperatures (higher than 200–600 °C), these sensors are limited in the practical applications.…”

Porous Tungsten Oxide: Recent Advances in Design, Synthesis, and Applications

“…WO 3 thin films were grown on quartz resonator and a quartz crystal microbalance was used to monitor the sensing capability. The WO 3 film undergoes a fast reaction and shows improved sensitivity in online monitoring environmental samples without further modification [52a] . A thin film of nanocrystalline of WO 3 was grown on platinized‐silicon substrate using laser energy.…”