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A series of Zn"xMg"1"-"xGa"2O"4:Co^2^+ spinels (x=0, 0.25, 0.5, 0.75,
and 1.0) was successfully produced through low-temperature burning method
by using Mg(NO"3)"2.4H"2O, Zn(NO"3)"2.6H"2O, Ga(NO"3)"3.6H"2O, CO(NH"2)"2,
NH"4NO"3, and Co(NO"3)"2.6H"2O as raw materials. The product was
characterized by X-ray diffraction, transmission electron microscopy, and
photoluminescence spectroscopy. The product was not merely a simple mixture
of MgGa"2O"4 and ZnGa"2O"4; rather, it formed a solid solution. The lattice
constant of Zn"xMg"1"-"xGa"2O"4:Co^2^+ (0@?x@?1.0) crystals has a good
linear relationship with the doping density, x. The synthesized products
have high crystallinities with neat arrays. Based on an analysis of the
form and position of the emission spectrum, the strong emission peak around
the visible region (670nm) can be attributed to the energy level transition
[^4T"1(^4P)->^4A"2(^4F)] of Co^2^+ in the tetrahedron. The weak emission
peak in the near-infrared region can be attributed to the energy level
transition [^4T"1(^4P)->^4T"2(^4F)] of Co^2^+ in the tetrahedron.
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