M:MgAl_2O_4(M=Mn,Cr)的发光性质及能量传递

Luminosity and Energy Transfer of M:MgAl_2O_4(M= Mn,Cr)

采用化学共沉淀法制备出单掺Mn^(2+),单掺Cr^(3+)以及Mn^(2+),Cr^(3+)双掺的镁铝尖晶石粉体,改变各掺杂离子浓度,对粉体进行XRD、荧光分析。结果表明,单掺Mn^(2+)离子的样品在450nm波长激发下发射520nm的绿光;单掺Cr^(3+)离子的样品在425nm和545nm波长激发下发射694nm的红光;双掺的Mg1-xAl2(1-y)O4:xMn^(2+),yCr^(3+)粉体在激发波长为450nm时得到525nm的绿光和694nm的红光,双掺样品在694nm的红色发射峰由425nm,450nm和525nm共同激发,Mn^(2+)和Cr^(3+)离子之间存在能量传递,二者互为激发中心和敏化中心,随着Mn^(2+)离子和Cr^(3+)离子浓度的增加,发射光谱中发生猝灭时的绿光强度得到提高,红光强度逐渐增加。

Solely doped Mn 2+,Cr 3+and magnesium aluminate spinel powder with double-doped Mn 2+,Cr 3+is prepared with chemical coprecipitation method,every kind of ionic concentration is changed,the power is applied with XRD and fluorometric analysis.The result shows that the sample with solely doped Mn 2+ionic emitted 520 nm of green light under the excitation of 450 nm wavelength;the sample with solely doped Cr 3+ionic emitted red light of 694nm under the excitation of 425 nm and 545 nm;double-doped Mg 1-x Al 2(1-y)O 4:x Mn 2+,y Cr 3+powder can get green light of 525 nm and red light of 694 nm when emitting wavelength is 450 nm,red emission peak of double-doped sample at 694 nm is excitated together with 425nm,450 nm and 525 nm,there is energy transfer between Mn 2+and Cr 3+,both are excitation center and sensitivity center.With concentration increasing of Mn 2+and Cr 3+,green light intensity in emission spectrum is increased,as well as red light.