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Undoped and Ce and Eu doped glasses and glass ceramic materials with nominal composition 33 % PbO 67 % B203 (% in mol), were obtained by melting/quenching technique. Glass ceramics were obtained by subsequent crystallization of glass samples. Glass samples were characterized by Inductively Coupled Plasma (ICP), Differential Thermal Analysis (DTA), Fourier Transform Infrared Spectrometry (FTIR) and UV-Vis spectrometry. Glass-ceramics were characterized by X-Ray Powder Diffraction, and by measuring their therluminescence response as a function of 90 Sr irradiation dose. from a lead borate glass intended for thermoluminescence dosimetry, as far as to study the effects that crystallization and Eu and Ce doping produce on their thermoluminescence response. PbB407 was found as the only crystalline phase in doped and undoped glass ceramics. Ce-doping was found to give a narrower bandgap than Eu one, and also introduces new electronical states. Crystallization clearly increases the thermoluminescence response, while undoped material gives higher response up to 20 Gy, although Ce-doping gives linearity up to 35 Gy and a higher response above 20 Gy. Among the studied samples, lead borate glass-ceramics, Ce-doped and undoped, present the best performance and they are then promising materials for thermoluminescence dosimetric applications.

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Recently inorganic perovskites have had a deep impact in perovskites-based devices allowing the fabrication of high efficiency and high stability devices. To continue with the development of these technologies a detailed study of the optoelectronic properties of these materials is necessary since this is a fundamental tool for the design of new and more efficient devices. In the present work, the optical properties of γ-CsPbI3 nanoparticles are studied using temperature dependent spectroscopic techniques of transmittance and photoluminescence. The absorption spectrum shows a marked excitonic behavior especially at low temperatures. Analyzing this spectrum with the Elliot function the evolution with temperature of the bandgap and the exciton binding energy is studied. From the evolution of the shape of the excitonic peak, both in the absorption and photoluminescence, we determined the excitonic recombination nature of photoluminescence and exciton-phonon interaction energy. Once proven the excitonic nature of photoluminescence we prove that the Stokes Shift has its origin in excitonic thermalization. Finally, analyzing the low energy region of the absorption spectrum the Urbach energy was determined. The obtained values, which are very low for solution processed nanoparticles, indicates that the nanoparticles present excellent crystallinity and are suitable for the implementation of quantum electronic devices.

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