Co-precipitation reaction followed by hydrothermal treatment were used to synthesise Eu 3+ or Tb 3+ doped LaPO 4 nanorods, of 5-10 nm in width and 50-100 nm in length. Surface modification of the as-prepared nanoparticles with a selected luminescent organic compound resulted in formation of hybrid inorganicorganic nanomaterials. The products obtained exhibited tunable multicolour luminescence, dependent on the surface modification and applied excitation wavelength. The colour of their emission can be altered from red-orange to yellow-green. Powder X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) confirmed the structure and morphology of the products synthesized. Successful surface modification of the nanophosphors was evidenced by analytical and spectroscopic techniques such as dynamic light scattering (DLS)providing size distribution histograms and zeta potentials of the nanoparticles; IR spectroscopy and elemental analysis which proved the presence of an organic phase in the structure; spectrofluorometry (excitation/emission spectra and luminescence decay curves) which confirmed the formation of hybrid, surface modified nanomaterials revealing tunable multicolour emission.

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Mesogenic dibenzophenazine derivatives have been synthesized and their liquid crystalline, fluorescent and electrochemical properties have been studied. All compounds form the Col phase, one of them (4-hydroxyphenyl 2,3,6,7-tetrakisoctyloxy-dibenzo[a,c]phenazine-11-carboxylate, 4) additionally shows an unusual columnar structure with p2mg symmetry, which is a partially lamellarized columnar phase. The emission spectra exhibit a huge Stokes shift that is due to the different molecular conformation in ground and excited states. The non-dispersive hole transport current under UV laser illumination was observed and the charge mobility in the range 10-10 cm V s was determined with the time of flight (ToF) method. The measurements have been interpreted according to the Gaussian disorder model, providing material parameters that reflect the energetic distribution of localized states (diagonal disorder, σ) and distribution of coupling parameters between transport sites (off-diagonal disorder, Σ).

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