【摘 要】
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A series of Eu2+ doped and Eu2+/Mn2+ co-doped Mg0.695Si0.695Al1.39O3.65N0.35 (MSAON) phosphors were synthesized by solid-state reaction at a lower temperature o
【机 构】
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College of Optical and Electronic Technology,China Jiliang University,Hangzhou 310018,China;Institut
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A series of Eu2+ doped and Eu2+/Mn2+ co-doped Mg0.695Si0.695Al1.39O3.65N0.35 (MSAON) phosphors were synthesized by solid-state reaction at a lower temperature of 1500 ℃.The crystal morphology and structure of MSAON host were characterized by SEM,TEM and XRD.The quantum yield (QY) for Eu2+doped MSAON phosphors was measured as high as 62％,indicating the excellent luminous efficiency.For the Eu2+/Mn2+ co-doped MSAON phosphor,the photoluminescence spectrum and delay curves reveal the efficient energy transfer (ET) process from Eu2+ to Mn2+ ions.Meanwhile,the corresponding energy transfer efficiency,critical distance and mechanism are discussed in detail.Temperature-dependent emission spectrum shows the thermal and color stabilities.The emission color of MSAON∶Eu2+,Mn2+phosphors could be tuned from blue through white to red via varying the concentration of Mn2+ ions.White-light-emitting diodes (WLEDs) were successfully fabricated by encapsulating the phosphors in n-UV LED (365 nm) devices obtaining white light with color rendering index (CRI) as high as 87.7.The results reveal that the MSAON∶Eu2+,Mn2+ phosphors could have potential application in the field of n-UV WLEDs.
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