In Situ Embedding Synthesis of CsPbBr 3 @Ce-MOF@SiO 2 Nanocomposites for High Efficiency Light-Emitting Diodes: Suppressing Reabsorption Losses through the Waveguiding Effect.
Jiejun RenAndries MeijerinkXiaopeng ZhouJiapeng WuGangyi ZhangYuhua WangPublished in: ACS applied materials & interfaces (2022)
All-inorganic perovskite quantum dots (PQDs), which possess outstanding photophysical properties, are regarded as promising materials for optoelectronic applications. However, the poor light conversion efficiency and severe stability problem hinder their widespread applications. In this work, a novel encapsulation strategy is developed through the in situ growth of CsPbX 3 PQDs in presynthesized mesoporous cerium-based metal organic frameworks (Ce-MOFs) and further silane hydrolysis-encapsulation, generating stable CsPbX 3 @Ce-MOF@SiO 2 composites with greatly enhanced light conversion efficiency. Moreover, the simulation results suggest that the pore boundary of Ce-MOFs has a strong waveguide effect on the incident PQD light, constraining PQD light inside the bodies of Ce-MOFs and suppressing reabsorption losses, thus increasing the overall light conversion efficiency of PQDs. Meanwhile, the Ce-MOF@SiO 2 protective shell effectively improves the stability by blocking internally embedded PQDs from the harmful external environment. Further, the obtained white-light-emitting diode shows an ultrahigh luminous efficiency of 87.8 lm/W, which demonstrates their great potential in optoelectronic applications.