Institute of Advanced Materials (IAM), Nanjing Tech University, Nanjing, 211816, China.
School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot, 010021, China.
Angew Chem Int Ed Engl. 2023 Jul 3;62(27):e202303482. doi: 10.1002/anie.202303482. Epub 2023 May 23.
Although large amount of effort has been invested in combating thermal quenching that severely degrades the performance of luminescent materials particularly at high temperatures, not much affirmative progress has been realized. Herein, we demonstrate that the Frenkel defect formed via controlled annealing of Sc (WO ) :Ln (Ln=Yb, Er, Eu, Tb, Sm), can work as energy reservoir and back-transfer the stored excitation energy to Ln upon heating. Therefore, except routine anti-thermal quenching, thermally enhanced 415-fold downshifting and 405-fold upconversion luminescence are even obtained in Sc (WO ) :Yb/Er, which has set a record of both the Yb -Er energy transfer efficiency (>85 %) and the working temperature at 500 and 1073 K, respectively. Moreover, this design strategy is extendable to other hosts possessing Frenkel defect, and modulation of which directly determines whether enhanced or decreased luminescence can be obtained. This discovery has paved new avenues to reliable generation of high-temperature luminescence.
尽管已经投入了大量的努力来对抗严重降低发光材料性能的热猝灭，尤其是在高温下，但并没有取得太多肯定的进展。在这里，我们证明了通过控制 Sc（WO ）的退火形成的弗伦克尔缺陷：Ln（Ln=Yb、Er、Eu、Tb、Sm），可以作为能量库，并在加热时将存储的激发能回传给 Ln。因此，除了常规的抗热猝灭外，在 Sc（WO ）：Yb/Er 中甚至获得了热增强的 415 倍的下转换和 405 倍的上转换发光，这分别创下了 Yb-Er 能量转移效率（>85%）和工作温度为 500 和 1073 K 的记录。此外，这种设计策略可扩展到其他具有弗伦克尔缺陷的宿主，其调制直接决定了是否可以获得增强或减弱的发光。这一发现为可靠地产生高温发光开辟了新途径。
