Abstract
Nanocrystalline Nb2O5 films were prepared by an extended sol-gel method. The synthesis is based on the hydrolysis of a modified Nb-alkoxide precursor. Reaction of the modified precursor (Nb(OEt)5 + 2 2,4-pentanedione) with water in ethanol leads to a homogeneous hydrolyzed solution, which is stable against precipitation of niobium oxide after evaporation of the ethanol and in the whole pH-range investigated (1–10). Autoclaving leads to amorphous gels, from which homogeneous nanocrystalline niobium oxide films of up to 15 μm can be made. During annealing crystalline phases are first observed above 500°C with fully crystalline films of orthorhombic T-phase Nb2O5 attained at 600°C. The microstructural, crystallographic, optical and photoelectrical properties of the films were characterized by means of SEM, XRD, UV-VIS spectroscopy and surface photovoltage spectroscopy, respectively.
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Lenzmann, F., Shklover, V., Brooks, K. et al. Mesoporous Nb2O5 Films: Influence of Degree of Crystallinity on Properties. Journal of Sol-Gel Science and Technology 19, 175–180 (2000). https://doi.org/10.1023/A:1008767717625
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DOI: https://doi.org/10.1023/A:1008767717625