通过457 nm和915 nm连续激光器对固相反应法和溶胶-凝胶法制备的YAG: Ce, Yb荧光粉中的Yb3+近红外发光和可见上转换发光能量转移机制进行了研究。两种激发下, 溶胶-凝胶法样品的近红外发光猝灭浓度均在5%左右, 发光强度变化曲线趋势相近; 固相反应法产物, 915 nm直接激发猝灭浓度为5%左右, 457 nm间接激发猝灭浓度为10%左右, 说明固相反应法掺杂离子分布更不均匀。样品中存在来自Yb3+到杂质离子间能量传递和Yb3+-Yb3+离子对的两种上转换发光; 固相反应法产物Yb3+-Yb3+离子对协同发光强于溶胶-凝胶法产物, 说明Yb3+离子簇集现象较为明显, 可能降低此类材料的实际近红外转换效率。

457 nm and 915 nm continuous lasers were used to study the Yb3+ near-infrared luminescence and up-conversion energy transfer mechanisms in YAG:Ce, Yb phosphors synthesized via solid-state reaction and sol-gel method. Under either excitation, sol-gel samples demonstrated the same Yb3+ near-infrared luminescence quenching concentration of -5%, with similar trends. In solid-state reaction samples, 915 nm excitation yielded a quenching concentration of -5%, while 457 nm excitation resulted in a quenching concentration of 10%, indicating a less homogeneous distribution of dopant ions. Visible up-conversion luminescence from Yb3+-impurity ion and Yb3+-Yb3+ ion pairs can be observed. Solid-state reaction samples demonstrate stronger cooperative luminescence from Yb3+-Yb3+ ion pairs. The results show that clustering of Yb3+ ions is more significant in samples synthesized via solid-state reaction, which could lower the near-infrared down-conversion efficiency of this type of material.