Abstract: Gas sensor devices based on WO3 particles, nanoneedles and gold functionalized
nanoneedles were developed. The devices were fabricated on classical ceramic substrates
and the sensor response characterized to a wide range of analytes. All sensors revealed
optimum operating temperatures below 250ºC and good sensitivities to ethanol, hydrogen
and nitrogen dioxide. In particular the nanoneedle structures showed good sensitivity to
low ethanol concentrations (1.5 ppm), with the gold functionalized structures having
improved sensitivities compared to the non-functionalized structures.
Abstract: This article reports SnO2 deposition by Aerosol-Assisted Chemical Vapour Deposition (AACVD), from tin complexes: [Sn(18-Cr-6)Cl4] and [Sn(H2O)2Cl4](18-Cr-6). The structure and properties of the precursors, used to synthesize SnO2 layers by AACVD for the first time, were characterized with the help of XRD, IR and TGA. Each complex was deposited by AACVD at 250, 400 and 500 ºC in the flow of N2. The resulting films were studied by XRD and AFM techniques. Gas sensing properties of the deposited layers were tested towards 10ºppm NO2 in air. The maximum sensor response to the analyte was measured at 300ºC.
Abstract: We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol
assisted chemical vapour deposition (AACVD) and characterised them using scanning electron
microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron
spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM
shows that both the needles and the gold particles are crystalline. XPS indicates the presence of
oxygen vacancies, i.e. the films are WO3-x, and hence the deposited material is composed of
semiconducting nanostructures and that the interaction between the gold particles and the WO3
needles surface is weak.
Abstract: A new method of synthesising nanoparticle-functionalised nanostructured materials via Aerosol Assisted Chemical Vapour Deposition (AACVD) has been developed. Co-deposition of Au nanoparticles with WO3 nanoneedles has been used to deposit a sensing layer directly onto gas sensor substrates providing devices with a six-fold increase in response to low concentrations of a test analyte (ethanol).
Abstract: Aerosal Assisted Chemical Vapour Deposition (previous termAACVD)next term was implemented to grow WO3 layers with nanoneeddle-like morphology onto gas sensor alumina substrates from a W(OPh)6 precursor. A variety fo solvents and deposition temperatures in a range of 350 ring operatorC and 500 ring operatorC were used in order to find th eoptimal deposition conditions. The obtained WO3 structure was doped with gold particles by rf sputtering. The WO3 gas sensor based on nanoneedles showed high selectivity against to NO2. The sensing properites of WO3 nanoneedle-like structure, as well as influence of gold doping in their sensing properties were examined in this work.
