In materials science, one of the main topics of research is the relationship between the morphology of a material and its properties, as the materials size, shape, surface properties, etc can greatly influence the suitability for its final use in a commercial product. The knowledge of the structure property relationship and controlling the structure via different preparative techniques to achieve the desired properties is of vital importance in many branches of science and engineering. The so called advanced materials are used as catalysts, sensors, in separation processes, energy production and storage systems as for example fuel cells and accumulators – batteries. One of the many synthesis techniques is hydrothermal synthesis, in which crystals are grown in an aqueous medium at an elevated temperature and pressure.
One of many materials is niobium pentoxide, which is used in catalysis, electrochromic and photoelectrochemical devices, etc. Nb2O5 crystallises in many polymorphic forms, simillarly as TiO2 which is subject to rigorous amounts of research due to its photocatalytic properties. Previous research on TiO2 observed the phenomena of crystal twinning, where two crystals share points of the same crystal lattice in a symmetrical manner. The twin crystals grow along a twinning plane. Crystal twinning is cause to a higher specific surface area of the material compared to single crystals, which is often desired for specific uses.
On the basis of “closeness” of titanium and niobium in the periodic table of elements we speculate that the preparation of niobium oxide twins through hydrothermal synthesis might be possible. Furthermore, due to the simillarity in atomic radii of both elements, potential combinations of oxides could be an interesting topic of research
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