Search

All-inorganic halide perovskite quantum dots (QDs) have recently received much attention due to their excellent optoelectronic properties. And their emission properties still need to be improved for further applications. Here, we demonstrated a remarkable emission enhancement of the CsPbBr 3 QDs based on an Ag nanoparticle-Ag film plasmonic coupling structure. Through precise control of the gap distance between Ag nanoparticle and Ag film, the localized surface plasmon resonance (LSPR) peak was tuned to match the emission wavelength of the CsPbBr 3 QDs. We achieved a 30-fold fluorescence intensity enhancement and a lower lasing threshold, which is 25% of that of the CsPbBr 3 QDs without plasmonic coupling structure. It is attributed to that the plasmonic coupling structure exhibits an extremely strong local electric field owing to the coupling between LSPR of Ag nanoparticle and surface plasmon polariton of Ag film. This work provides an effective way to enhance the optical emission of perovskite QDs and promotes the further exploration of on-chip light source.

All-inorganic halide perovskite CsPbX 3 (X = Br/Cl/I)quantum dots have gained a considerable attention in the optoelectronic fields. However, the high cost and poor stability of the prepared CsPbX 3 quantum dots (QDs) are inevitable challenges for their future practical applications. And the high-performance CsPbX 3 QDs are always needed. Herein, a facile and low-cost synthesis scheme was adopted to prepare the CsPbBr 3 QDs modified by lead bromide (PbBr 2 ) and tetraoctylammonium bromide (TOAB) ligands at room temperature in open air. The prepared CsPbBr 3 QDs exhibited a high photoluminescence quantum yield (PLQY) of 96.6% and a low amplified spontaneous emission (ASE) threshold of 12.6 µJ/cm 2 . Stable ASE intensity with little degradation was also realized from the CsPbBr 3 QDs doped with PMMA. Furthermore, the enhanced ASE properties of the CsPbBr 3 QDs-doped PMMA based on distributed feedback (DFB) substrate was achieved with a lower threshold of 3.6 µJ/cm 2 , which is 28.6% of that of the (PbBr 2  + TOAB)-treated CsPbBr 3 QDs without PMMA. This work exhibits a promising potential in the on-chip light source.