The main interests of the group in phosphate glasses deal with their applications in optics and energy fields. On the one hand, neodymium doped phosphate glasses are currently the best solution as hosts for high energy and high power lasers, though the production of big and homogeneous specimens requires of very special conditions. Furthermore, small amounts of retained water conduct to important deteriorating effects from the quenching of the Nd luminescence. We have recently demonstrated that a very efficient dehydroxylation method of the phosphate glasses may be obtained by re-melting the glass under a reducing or inert atmosphere [Muñoz, Int. J. App. Glass Sci. (2019)]. This new processing technique allows to obtain glasses with high optical homogeneity and absorption coefficients of hydroxyl ions below 2 cm-1. The luminescence behaviour of Nd3+ ions has shown optimal results for their application as high power laser glasses, and the thermal and mechanical properties of the currently studied alumina-containing glasses have comparable values to those of commercial laser glasses, proving that the employed method of dehydroxylation may be a promising alternative for their production.

On the other hand, phosphate glasses are well known for their high dissolution rates in aqueous media though, nevertheless, they have found relevant technological applications as low temperature sealing glasses, matrices for the immobilization of radioactive wastes or as laser hosts as mentioned above. Another way to improve their durability is through nitridation, where part of the oxygen is substituted by nitrogen atoms by means of thermal ammonolysis reactions under NH3 flow. As a consequence, the dissolution rate can be decreased by orders of magnitude at the same time that other properties are improved, such as hardness, thermal and mechanical resistance and ionic conductivity [Muñoz et al., Solid State Ionics 179 (2008) 574], having found application as solid electrolytes in lithium secondary batteries when processed as thin-films as the so-called LiPON electrolytes [Yu, J. Electrochem. Soc., 144(2) (1997) 524].

Finally, great attention is also paid to the study of the relationships between the properties of the glasses and their atomic structure and thermodynamics, conducting basic research onto a range of topics such as the viscous behaviour, glass-forming ability and the prediction of their properties [Dagupati et al. Mat. Chem. Phys., 258 (2021) 123941].


Nd-doped phosphate laser glasses