Water-stable and ion exchange-free inorganic perovskite quantum dots encapsulated in solid paraffin and their application in light emitting diodes.

Perovskite quantum dots (PQDs) with high quantum efficiency and broad spectral tunability are promising luminescent materials and show potential applications in light-emitting diodes (LEDs). However, PQDs degrade rapidly in atmosphere moisture due to their easy hydrolysis and undergo undesirable spectral changes associated with ion exchanges. Herein, we encapsulated blue, green and red fluorescence-emitting all-inorganic PQDs respectively with hydrophobic solid paraffin to obtain multi-color luminescent paraffin-PQD composites (P-PQDs). The P-PQD composites not only preserve the bright luminescence, but also greatly improve the water resistance of PQDs. Moreover, the anion exchange phenomenon is effectively inhibited for the isolation of PQD nanoparticles by a solid paraffin layer. Finally, blue, green and red luminescent P-PQD microparticles have been synthesized and show promising applications in LEDs.