“…12,13 Mn 4+ ion can usually be stable | 5911 CAO et Al. in octahedral environments and substitute for the Al 3+ , Sc 3+ , Ga 3+ , Ti 4+ , Si 4+ , Ge 4+ , Zr 4+ , Sn 4+ , Ta 5+ , Nb 5+ , Sb 5+ , Te 6+ , Mo 6+ , and W 6+ sites in octahedral cell and form the octahedral center in host lattice. [14][15][16][17][18][19][20][21][22][23][24][25][26][27] The luminescence properties of Mn 4+ -doped phosphors can be affected by the co-valency of the "Mn 4+ -Ligand" bonding and the host crystal field environment. Up to now, there are two main kinds of hosts for Mn 4+ doping, such as fluorides and oxides.…”