Concentration dependent cyan emission by europium-doped borosilicate glasses.

At present, doping of different alkaline-earth metal ions is mainly used to tune the emission peak of europium (Eu) ions in glasses. However, the optimization of Eu-doped glasses is hindered due to limited discussion on the relationship between local glass network structure, concentration of Eu ion dopants, and visible light emission by Eu ions. In this study,we prepared two series of borosilicate glasses doped with Eu ions, by varying the ratio of SiO₂ to B₂O₃ and adjusting the concentration of Eu ion dopants to obtain cyan emission. The optical properties, structure, and differential scanning calorimetry (DSC) of the investigated glasses were systematically studied. With gradual increase in the content of SiO₂, red shifting from 471 nm to 492 nm was observed under excitation at 410 nm, with the introduction of Eu₂O₃ also causing a redshift from 471 nm to 488 nm. The spectral results also revealed that under excitation at 410 nm all the glass samples exhibited cyan emission, with the optimal cyan peak at 492 nm (Si-45) and the strongest cyan emission at Eu-0.4 (480 nm). By adjusting the concentration ratios of Si to B in europium-doped borosilicate glass, it was observed that by altering the [SiO₄] tetrahedra, [BO₄] tetrahedra, and [BO₃] triangles within the glass ultimately cyan emission can be achieved. By varying the doping concentration of Eu ion to change the degree of local Eu ion clustering in the glass system, cyan emission can be achieved by tuning the emission peak. [ABSTRACT FROM AUTHOR]