[en] Full text: Luminescent complexes of rare earth have been extensively studied in different fields of research improving the industrial development of these materials for their utilization as electroluminescent displays, catalysts, and biomaterials. The interest in rare earth compounds having aromatic ambidental ligands has increased since it was found that they can act as light collectors (antenna effect), thus bypassing the weak absorption of the lanthanides and resulting in highly efficient luminophores. In this work ZrO₂ was prepared by the hydrothermal microwave method (HMM) at 140 deg C for 32 min. The hybrid material was obtained using the previous ZrO₂ dispersed in distilled H₂O, which was added Eu⁺³ and the 3-hydroxypicolinamide (Hhpa) followed by stirring for about 3 hours. The material was analyzed by X-ray diffraction (XRD), Transmission electron microscopy (TEM), diffuse reflectance spectroscopy (UV-vis.). The photoluminescent properties were investigated through their excitation and emission spectra and gas sensor studies were also performed. It was observed completely crystalline powders for all materials, were XRD peaks were perfectly indexed to the tetragonal phase of ZrO₂ (JCPDS 50-1089). TEM micrographs reveal a spherical nanostructure pattern presenting an average diameter of 4 nm. The UV-vis. absorption was used to determine the band gap. Excitation and emission spectra revealed the characteristic peaks of the Eu³⁺ transitions. The studies of this material as gas sensors showed a significative change in the electric resistance for the hybrid material. References: [1] I.L.V.Rosa, P.C.de Sousa Filho, C.R.Neri, O.A.Serra, A.T.Figueiredo, J.A.Varela, E.Longo. J Fluoresc 21 (2011), 1575. [2] S. Jianliang, H.Ge, S.Qing, Z.Zhaohong, G.Lei. Spectrochim. Acta, Part A 91 (2012), 192. (author)