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Aerosol assisted chemical vapour deposition (AACVD) reactions of tungsten hexacarbonyl, [W(CO) 6 ], in acetone, methanol, acetonitrile and a 50 : 50 mixture of acetone and toluene resulted in the deposition of blue partially reduced WO 32x films which showed preferred orientation along the (0 1 0) direction. Films deposited solely from toluene, however, were composed of a mixture of tungsten metal and W 3 O. All films could be annealed to yellow randomly orientated crystalline monoclinic WO 3 . The films deposited from methanol had a morphology comprising of a network of randomly orientated needles, which is strikingly different to the agglomeration of spherical particles observed with the other solvents. The WO 3 films functioned as gas sensitive resistors for the detection of NO 2 . Responses were recorded at minimum concentrations of 1.03 ppm of NO 2 , significantly exceeding those of commercial screen printed sensors.

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The use of constructed wetlands (CWs) is a promising approach for the remediation of wastewater. The present study aims to develop a plant-bacteria system within CWs for the efficient remediation of tannery effluent. In a vertical-flow CW vegetated with Leptochloa fusca (Kallar grass), a consortium of three different endophytic bacteria, Pantoea stewartii ASI11, Microbacterium arborescens HU33, and Enterobacter sp. HU38, was used for bioaugmentation. CWs vegetated with only L. fusca had the potential to remediate tannery effluent, but augmentation with endophytic bacteria enhanced the growth of L. fusca while aiding in the removal of both organic and inorganic pollutants from the tannery effluent. Moreover, the bacterial augmentation decreased toxicity in the effluent as well. A higher number of chromium (Cr)-resistant bacteria were isolated from the rhizosphere and endosphere of L. fusca inoculated with the endophytes than from uninoculated plants. Due to promising bioremediation and detoxification potential of L. fusca, it is reported for the first time as a potential candidate to develop effective CWs for the remediation of polluted effluents in combination with pollutant-degrading endophytic bacteria.

Aerosol assisted chemical vapour deposition (AACVD) of molybdenum polyoxometallates dissolved in acetonitrile or water yielded adhesive thin films of molybdenum oxides on glass. At substrate temperatures of 300-350 uC single phase MoO 3 was obtained, from 350-500 uC mixed phases of MoO 3 -MoO 2 were formed and at 500-550 uC single phase MoO 2 was observed. The morphology of the as-deposited molybdenum oxide films was found to be dependent upon a number of factors including the nature of the precursor used, the deposition temperature and position of the film within the reactor. Needles, spheres, agglomerates and platelets formed depending on the conditions. The films with a needle-like microstructure displayed enhanced hydrophobicity to water droplets (125u contact angle). X-Ray diffraction showed that the MoO 3 films had typical cell constants of a = 3.96, b = 13.85, c = 3.69 A ˚and the MoO 2 films had typical cell constants of a = 5.62, b = 4.84, c = 5.56 A ˚, b = 119.32u. The MoO 2 films were readily converted to MoO 3 by annealing in air for 30 minutes at 600 uC. The MoO 3 films functioned as gas sensors showing a linear change in electrical resistance upon exposure to trace amounts of ethanol vapour in air.