| abstract |
A process for preparing a Mn +4 doped phosphor of formula I n A x [MF y ]:Mn +4 In n includes combining a first solution comprising a source of A and a second solution comprising H 2 MF 6 in the presence of a source of Mn, to form the Mn +4 doped phosphor; whereinn A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is the absolute value of the charge of the [MF y ] ion; y is 5, 6 or 7; andn nwherein a value of a Hammett acidity function of the first solution is at least −0.9.n nn Particles produced by the process may have a particle size distribution with a D 50 particle size of less than 10 μm. |