Mn4+-activated BaSiF6 red phosphor: Hydrothermal synthesis and dependence of its luminescent properties on reaction conditions

• The crystal structure of BaSiF6:Mn4+ has been verified using Rietveld refinement.
• The optimum hydrothermal reaction condition for BaSiF6:Mn4+ has been confirmed.
• The white LED based on YAG:Ce–BaSiF6:Mn4+ mixture presents warmer white light than that only with YAG:Ce.

In this work, a series of BaSiF6:Mn4+ red phosphors were synthesized through a hydrothermal route. The crystal structure and morphology were characterized by powder X-ray diffraction (XRD) with Rietveld refinement, scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS) in detail. The influence of reaction conditions, including the concentration of KMnO4 and HF, reaction temperature and time, on the photoluminescence properties were investigated systematically. It can emit intense red light (∼636 nm) under blue light (∼458 nm) illumination. The white LED device based on YAG:Ce–BaSiF6:Mn4+ mixture shows warm white light with low color temperature and high correlated color index, which reveals its potential application in WLED.