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TiO2 thin films prepared by sol–gel synthesis were N-doped by post treating with liquid ammonia and annealing at 500 °C. Characterisation by X-ray diffraction and Raman spectroscopy confirmed that the anatase crystal type was retained and present in all samples. Scanning electron microscopy showed that treatment with liquid ammonia had no significant effect on the film morphology. Functional testing under filtered while light conditions involving water contact angle, and the photo destruction of both Resazurin and Stearic acid showed the ammonia treated samples to be active visible light photocatalysts in contrast to the pure TiO2 and the blank controls. X-ray Photoelectron Spectroscopy studies indicate the presence of interstitial nitrogen (N1s = 400 eV) suggesting that the origin of the enhanced photocatalytic activity is most likely due to oxygen vacancies created by the interstitial nitrogen incorporation. This synthesis method utilises a simple, inexpensive and highly effective post treatment route to N-dope TiO2 and produces visible light photocatalysts with potential applications in self-cleaning and healthcare environments.

Nanocrystalline anatase (TiO2) thin films prepared by a physical vapour deposition method were nitrided by annealing in flowing NH3 at temperatures ranging between 650 °C and 700 °C. It was established that there was a narrow window of temperatures which allowed both incorporation of interstitial nitrogen into the films with retention of the anatase phase without chemical reduction and preservation of the characteristic nanocrystalline morphology. These optimally modified films responded to visible light in photowetting tests and showed the ability to degrade an organic dye under visible light irradiation. © 2011 Elsevier B.V. All rights reserved.

Atmospheric pressure chemical vapour deposition of tin monoselenide and tin diselenide films on glass substrate was achieved by reaction of diethyl selenide with tin tetrachloride at 350–650 °C. X-ray diffraction showed that all the films were crystalline and matched the reported pattern for SnSe and/or SnSe2. Wavelength dispersive analysis by X-rays show a variable Sn:Se ratio from 1:1 to 1:2 depending on conditions. The deposition temperature, flow rates and position on the substrate determined whether mixed SnSe–SnSe2, pure SnSe or pure SnSe2 thin films could be obtained. SnSe films were obtained at 650 °C with a SnCl4 to Et2Se ratio greater than 10. The SnSe films were silver–black in appearance and adhesive. SnSe2 films were obtained at 600–650 °C they had a black appearance and were composed of 10 to 80 μm sized adherent crystals. Films of SnSe only 100 nm thick showed complete absorbtion at 300–1100 nm.

Thin films of In2O3 have been grown on Y-stabilised ZrO2(100) substrates by oxygen plasma assisted molecular beam epitaxy over a range of substrate temperatures between 650 °C and 900 °C. Growth at 650 °C leads to continuous but granular films and complete extinction of substrate core level structure in X-ray photoelectron spectroscopy. However with increasing substrate temperature the films break up into a series of discrete micrometer sized islands. Both the continuous and the island films have excellent epitaxial relationship with the substrate as gauged by X-ray diffraction and selected area electron diffraction and lattice imaging in high resolution transmission electron microscopy. © 2008 Elsevier B.V. All rights reserved.