Luminescence of M ions (M=C, Fe, Co, Ni, Mn, Ti) in a-Al2O3 phosphor

A polyacrylamide gel route is used to synthesize the alumina-based light-emitting material M: a-Al2O3 (M=C, Fe, Co, Ni, Mn, Ti). Sintering temperature, pH value, organic additive, chelating agent, C and metal salt can significantly effects the formation of rhombohedral a-Al2O3 phase. The structure analysis shows that the carbon, Ti, Co, Ni doped Al2O3 powders obvious suppress the formation of a-Al2O3, in contrast, the Fe, Mn doped Al2O3 can accelerate the formation of a-Al2O3. The carbon and metal salt introduction to the Al2O3 precursor solution obvious influenced the sample morphology, band-gap, color and photoluminescence properties. The results show that the carbon and metal salt introduced to Al2O3 precursor solution reduces the band-gap values and enhances the photoluminescence properties of M: a-Al2O3 powders. The photoluminescence mechanisms of M: a-Al2O3 powders have been discussed on the basis of the experimental results. The M: a-Al2O3 composites making them promising candidates as efficient light-emitting materials, pigments, photocatalysts and radiation detection including space dosimetry, environmental dosimetry, medical dosimetry and personal dosimetry.