Synthesis And Luminescence Of Mn Doped Gallium Aluminate Phosphor And Glass Ceramics Containing Gallium Aluminate Nanocrystals

Both ZnAl₂O₄ and ZnGa₂O₄ are typical spinel inorganic materials with excellent physical and chemical performances,such as good acid and alkali resistance,low temperature sintering and high quantum yield.Therefore,it has a wide and potential application prospect in transparent ceramic materials,optical materials and other fields.By changing the synthesis conditions and doping to form solid solution,we adjust the crystal structure of the matrix,so as to effectively improve its optical properties.Based on this point of view,this paper synthesized gallium zinc aluminate phosphor and the glass ceramics containing gallium zinc aluminate activated by manganese.And their luminescence is explored systematically.The results are as follows:1.The gap state and radius of zinc aluminate structure are discussed by the theoretical calculation and experiment.We use Li⁺with small ionic radius and Na⁺as charge compensation and dopant.These results show that Li⁺promotes the emission of Mn⁴⁺while Na⁺enhances the emission of Mn²⁺in the ZnAl₂O₄:Mn phosphor.With the change of Li⁺/Na⁺concentration,the ZnAl₂O₄:Mn sample presents a red or green spectral conversion,realizing the regulation of luminescence color.2.By replacing homologous atoms to form a solid solution,and changing the synthesis temperature,the spectral properties of ZnGa_2-xAl₂O₄:Mn phosphor prepared by high temperature solid state method were systematically studied.When the sintering temperature at 1250℃,the phosphor color changes from blue to green with the increase of Al³⁺:Ga³⁺ratio.When that is higher than 1250℃,the Mn⁴⁺emission peak in the red region shifts from 715 nm near infrared to 668 nm deep red.3.Mn activated ZnGa₂O₄/ZnAl₂O₄ nanocrystalline glass ceramics were fabricated by sol-gel method.The conditions,structure and spectral phenomena of nanocrystalline were discussed in detail.Interestingly,by controlling the Al³⁺content in the system and the annealing temperature,the glass ceramics emitting white light with high efficiency were successfully obtained.