采用高温固相法合成了Tb3+、Yb3+共掺杂的BaGd2ZnO5荧光粉。XRD测量数据表明合成的样品为纯相。在Tb3+特征激发(297 nm)下得到了Yb3+的特征发射(977 nm),并且对Tb3+与Yb3+能级图进行分析,证明Tb3+到Yb3+为合作能量传递。测量了不同Yb3+浓度下Tb3+的5D4能级(544 nm)的发光寿命曲线,计算得到Tb3+与Yb3+的能量传递效率和量子效率,最高量子效率为125.5%。Yb3+的发射与硅太阳能电池的吸收匹配,该材料有可能应用于硅太阳能电池以提高其转换效率。
Tb3 +and Yb3 +codoped BaGd 2 ZnO 5 phosphors were synthesized by high temperature solid-state method.Structures of the samples were investigated by X-ray diffraction.The excitation spectra and emission spectra were measured.With the increase of Yb3 +concentration,the visiable emission intensity decreases but the near-infrared emission increases.So the cooperative energy transfer from Tb3 +to Yb3 +is demonstrated.The luminesence lifetime decay curves of Tb3 +(544 nm) with different Yb3 +concentrations were measured.The dependence of lifetime,energy transfer efficiency and quantum efficiency on Yb3 +concentration were obtained.The highest quantum efficiency is 125.5%.The emission of Yb3 + 2F 5/2 →2F 7/2(977 nm) is just above the band gap of crystalline sillicon,so this material can be applied in the sillicon-based solar cells to progress the conversion efficiency.