用高温固相法合成了Yb3+、Bi3+共掺的YVO4,研究了BI3+的掺入对YVO4∶Yb3+发光光谱的影响和近红外发光的敏化作用.X射线衍射图谱研究表明:掺入Yb3+、Bi3+之后,基质YVO4的品格结构没有发生明显变化.Bi3+的掺入不仅显著增强了样品中yb3+的特征远红外发光强度,还使YVO4∶Yb3+激发光谱的范围红移,当Bi3+掺入的摩尔分数从0增加到0.05时,样品的最强激发峰位置从335 nm红移至352 nm,激发光谱范围由300-360 nm扩宽至300-430 nm.优化的Bi3+掺入量为0.03.初步讨论了VO3-4,Bi3+和Yb3+间的能量传递机理.结果表明Bi3+的共掺使YVO4∶Yb3+样品对长波紫外光的响应性能大大改善,作为一种基于量子剪裁的光谱转换材料,可以更好地匹配太阳光的能量谱,有助于提高硅太阳能电池的光电转换效率.%The near-infrared (NIR) luminescence phosphor Yb3+,Bi3+ co-doped YVO4 was prepared by a conventional solid state method and the sensitization of Yb3+ near-infrared luminescence by Bi3+ was investigated. By co-doping with Bi3+ from 0 to 0.05 the characteristic NIR luminescence of Yb3+ in the YVO4 matrix was greatly enhanced and the strongest site of the excitation wavelength red-shifted from 335 to 352 nm while the wavelength range of the excitation spectrum broadened from 300-360 to 300-430 nm. The optimized Bi3+ content is 0.03. The possible energy transfer mechanism among VO3- 4, Bi3+, and Yb3+ was discussed. We conclude that the NIR luminescence of YVO4:Yb3+ can be remarkably improved by co-doping with Bi3+ and its absorbance matches better with the solar energy spectrum. YVO4:Yb3+, Bi3+ is a promising spectral converter for silicon solar cells and it is expected to improve the photoelectric conversion efficiency.
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