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用高温固相法制备了蓝绿双色可调荧光粉Ba2Ca(BO3)2:Ce3+,Eu2+,Na+,并研究了其发光特性。在345 nm近紫外光激发下发射的分别以390和410 nm为主峰的蓝光发射带对应于Ce3+的5d→2F5/2和5d→2F7/2跃迁,峰值位于525 nm的绿光发射带归属于Eu2+的4f65d1→4f7跃迁。通过Dexter共振能量传递理论和Reisfeld近似计算得到2种离子之间存在四极矩-四极矩能量传递。当Ce3+和Eu2+的摩尔浓度分别为5%和4%时,样品的色坐标位置落在蓝绿色区域,并可以通过改变基质中Ce3+和Eu2+的摩尔比来调节荧光粉的色坐标。Ba2Ca(BO3)2:Ce3+,Eu2+,Na+是一种适用于近紫外芯片的新型双色可调谐白光LED用荧光粉。
The green and blue tunable phosphors Ba2Ca (BO3) 2: Ce3 +, Eu2 + and Na + were prepared by solid-state reaction at high temperature. Their luminescent properties were also studied. The blue emission bands at 390 nm and 410 nm, respectively, emitted by 345 nm near-UV excitation correspond to the 5d → 2F5 / 2 and 5d → 2F7 / 2 transitions of Ce3 +, and the green emission band with a peak at 525 nm belongs to 4f65d1 → 4f7 transitions of Eu2 +. Through the Dexter resonance energy transfer theory and the Reisfeld approximation, we can get the quadrupole - quadrupole moment energy transfer between two kinds of ions. When the molar concentrations of Ce3 + and Eu2 + are 5% and 4% respectively, the chromatic coordinate position of the sample falls in the cyan region, and the color coordinate of the phosphor can be adjusted by changing the molar ratio of Ce3 + and Eu2 + in the matrix. Ba2Ca (BO3) 2: Ce3 +, Eu2 +, Na + is a new type of two-color tunable white LED phosphor for near-UV chips.