Морфологические, структурные и оптические свойства микропорошков диоксида титана

Abstract

The work is devoted to a comprehensive experimental study of the morphology, structure and optical properties of titanium dioxide micropowders with several of modern analytical equipment. The method for obtaining photoluminescence (PL) and Raman scattering (RS) for titanium dioxide micropowders in microresonator cuvette (photon traps) was described. The powders consisting of close-packed particles in the shape of spherical particles of specified sizes (29-63 μm) were studied. In the photon traps, a certain mode is implemented, which is associated of trapping of the exciting radiation inside of device. It is shown that, at room temperature, intense photoluminescence in titanium dioxide micropowders (2.91 eV) was observed in excitation by the second optical harmonic (λ exc = 255.3 nm) of a copper vapor laser. It has been established that in micropowders of titanium dioxide micropowders in photon traps, is possible to observe the phenomenon of combination opalescence, which leads to the sharp (5–6 orders) increasing in the RS intensity in an ultradispersed medium. The high conversion efficiency of the exciting radiation into the RS signal is explained by the large value of the total path that the exciting radiation photon travels in the dispersed medium in the photon trap. It was found that an insignificant amount of silicon and aluminum impurities is present in titanium dioxide micropowders that not affect to formation of the photoluminescence band in the region of 2.91 eV. The developed method for recording PL and RS opens up wide possibilities for recording weak signals of secondary radiation that is important for inorganic and organic substances, as well as for creating small-sized laser analyzers of chemical compounds which is necessary for solving many practical problems.