Structural and chemical mechanism underlying formation of Zn2SiO4:Mn crystalline phosphor properties

Zn2SiO4:Mn crystalline phosphor is a substitutional solid solution Zn2-2xMn2xSiO4, with х≤0.13. As the number of activator ions x > 0.13 grows, the mechanism of defect formation changes: some manganese ions change from doubly charged to triply charged, which is accompanied by the emergence of vacancies in the zinc sublattice. It is demonstrated that the coordination number of Mn3+ ions in the structure of willemite is five. The concentration quenching of Zn2SiO4:Mn is associated with the oxidation of a part of activator ions and dissipation of excitation energy on structural defects. [Display omitted] •Change in nature of properties of Zn2-2xMn2xSiO4 with variation of x was established.•For x > 0.13 vacancies are formed in zinc sublattice due to transition of Mn2+ to Mn3+.•It was shown that coordination number of Mn3+ ions in structure of willemite is five.•Concentration quenching of luminescence of Zn2SiO4:Mn is due to oxidation of Mn ions.