Nanocomposites and nanomaterials

The results of various methods application for deposition of luminescent vanadate films 
Chukova O.1,  Nedilko S.A.1,  Nedilko S.G.1, Voitenko T.1, Androulidaki A.2, Manousaki A.2, Papadopoulos A.2, Savva K.2, Stratakis E.2
1 Taras Shevchenko National University of Kyiv, Volodymyrska Str., 64/13, Kyiv 01601, Ukraine. E-mail: chukova@univ.kiev.ua
2 Institute of Electronic Structure & Laser (IESL) of Foundation for Research & Technology Hellas (FORTH), Heraklion 711 10 Crete, Greece

Luminescent oxide films are widely used for optical material science needs; in particular, as luminescent converters for adaptation of incident solar light to spectral sensitivity of silicon solar cells and for converting of violet and blue LED radiation into white light. Oxide materials are characterized by high radiation and thermal stability that is important property for such applications. Luminescent emission of the oxide compound can be related with electronic transitions in their own molecular oxyaniones as well as with impure ions, especially RE ions. 
Row of the orthovanadate compounds is one of the best oxide matrices for luminescent RE ions. Our own studies have also shown that some of developed oxide compositions in the form of micro/nanoparticles are able to demonstrate promising optical and structural characteristics. In particular, we have developed vanadate nanoparticles with enhanced light harvesting from violet spectral range and intensive luminescence emission. The next important task is to save the obtained high optical characteristics of oxide nanoparticles under their incorporation of the synthesized vanadate nanoparticles into composite film coatings. Noted, that requirements to the properties of the films can be different for various practical tasks, therefore various methods of film application should be used in order to find the most suitable one for each practical application. 
The methods applied in this work for deposition of the vanadate films are spin-coating, solution evaporation and pulsed laser deposition. Advantages and disadvantages of the noted methods for growth of luminescent films from vanadate nanoparticles for various applications are studied and discussed.