Photoluminescence in Er-doped V2O5 and Er-doped CdV2O6

A group of samples from the CdO-V2O5 binary system, particularly with high V2O5 content, doped with Er3+ were prepared. The set of samples was fabricated using the conventional melt-quenching method. Depending on the proportion of the used reactants, the existence of V2O5 and of CdV2O6 was identified from X-ray diffraction measurements and Raman spectroscopy. Depending on the relative concentrations of CdO and V2O5, different types of morphologies for each sample were found in a scanning electron microscope. Their chemical composition was measured from energy dispersive spectroscopy in the same instrument. An effective Er-doping of the order of 1.0±0.35 at% was found for each sample. From optical absorption data, the composition dependent optical band gap was determined with values between 1.94 and 2.29 eV. Finally, photoluminescence experiments showed, in the samples with the highest V2O5 content, wide bands associated to oxygen vacancies. For the rest of the samples emissions from electronic transitions of Er3+ ions were detected.