Polycrystalline semiconducting oxide

Inorganic Gas response of polycrystalline semiconducting metal oxides Thermo-mechanical and thermo-chemical effects on percolation-dependent electron transport 41... 

Nanostructured materials fabricated by the aforementioned methods are usually amorphous, thus offering relatively poor properties. In order to improve, e.g., electrical properties in the case of semiconducting oxides, thermal crystallization at elevated temperatures has to be implemented, typically resulting in polycrystalline materials. 

Both HREELS and RAIRS have been applied extensively of the study of adsorbates on metal surfaces. The extension of the techniques to semiconducting or insulating oxide surfaces is hampered by a number of problems. The result is that until even relatively recently [9] there were only a couple of examples of RAIRS studies on oxides, and these were confined to polycrystalline systems. Most early HREELS studies were concerned with the characterisation of the intrinsic phonon modes of metal oxide surfaces. This contrasts strongly with the extensive literature concerning the vibrational characterisation of adsorbates and intermediates on powdered oxide surfaces that have been obtained by transmission or diffuse reflection IR techniques. 

Substrates, Films are usually prepared on platinum or gold electrodes which are inert, but semiconducting materials including indium tin oxide, n-type polycrystalline silicon, gallium arsenide, cadmium sulphide and cadmium selenide, graphite [38, 59], and oxide covered metals [60] have also been used. In the majority of cases, the films are produced readily and the only serious limitations are the potential and the nucleophilic nature of the solution. 

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