This work successfully verified that the addition of a flux (NH
4F, NH
4Cl, and H
3BO
3) during synthesis has an impact on the crystallite size and quantum efficiency of submicron-sized particles of CaMgSi
2O
6:Eu
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This work successfully verified that the addition of a flux (NH
4F, NH
4Cl, and H
3BO
3) during synthesis has an impact on the crystallite size and quantum efficiency of submicron-sized particles of CaMgSi
2O
6:Eu
2+ phosphors. The addition of NH
4F or NH
4Cl increased the crystallite size in the submicron-sized particles, yielding an increase in emission intensity and quantum efficiency. On the other hand, the use of the H
3BO
3 flux crystallized a secondary phase, SiO
2, and changed the lattice parameters, which degraded the luminescent properties. In addition, an excessive amount of NH
4Cl was examined, resulting in nucleation of a secondary phase, CaSiO
3, which changed the lattice parameters with no improvement in luminescent properties. These results demonstrate that the addition of a flux could be a method to improve the quantum efficiency of submicron-sized particles composed of nanocrystallites; however, a judicious choice of the flux composition and amount has to be carefully considered.
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