Optical performance of Mn4+ in a new hexa-coordinated fluorozirconate complex of Cs2ZrF6

In this work, a Cs2ZrF6:Mn4+ red phosphor, a novel and efficient supplement for commercial Y3Al5O12:Ce3+ type white light-emitting diodes (WLEDs), is successfully fabricated on a large scale through a cation exchange method using K2MnF6 as the Mn4+ source at ambient temperature. The crystal structure and morphology were characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), in detail. The complex is well crystallized in a single-phase with particulate morphology and presents sharp red emissions under blue light illumination. From the aspects of Ra and Tc, the optical performance of a WLED made with the Cs2ZrF6:Mn4+ red phosphor supplement is significantly improved and it can be used for indoor lighting applications.