Synthesis and photoluminescence properties of octahedral K2(Ge,Si)F6:Mn4+ red phosphor for white LED

PLE and PL spectra of K2GeF6:Mn4+ (λex=460 nm, λem= 631 nm) and K2(Ge,Si)F6:Mn4+ (λex=460 nm, λem=630 nm)