Controllable Synthesis and Tunable Colors of α- and β-Zn₂SiO₄:Mn²⁺ Nanocrystals for UV and Blue Chip Excited White LEDs

Green- and yellow-emitting α- and β-Zn 2 SiO 4:Mn 2+ nanocrystals incorporated into glass ceramics have been selectively synthesized successfully by a conventional melt-quenching method. XRD, EPR, TEM, EDS, and electronic optical spectroscopy were employed to discriminate the formation of α- and β-Zn 2 SiO 4:Mn 2+ nanocrystals and further to elucidate the coordination environment of Mn 2+ in the yellow-emitting Zn 2 SiO 4:Mn 2+ practical material. The combination of crystal field calculation with the experimental absorption and excitation spectra enables us to interpret optical spectroscopic features and therefore correlate the optical spectroscopy to the corresponding crystal structure. This work exemplified the correlation between the optical spectroscopy and coordination around the Mn 2+ ion and also shed light on the application of glass ceramics containing α- and β-Zn 2 SiO 4:Mn 2+ nanocrystals for UV and blue chip excited white LEDs.