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An ultrasonic synthesis method for high-luminance perovskite quantum dots

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Abstract

This work presents an ultrasonic synthesis method for perovskite quantum dots (QDs). The structure, particle size and morphology of perovskite quantum dots were analyzed, and the differences between the dispersion of the organic perovskite quantum dots prepared with and without the ultrasonic treatment were discussed. The results showed that the ultrasonic synthesis contributed to smaller particle sizes and a more uniform particle-size distribution. Tunable emission peaks and adsorption edges of CH3NH3PbX3 (X = Cl, Br and I) QDs prepared with different chemical compositions were also generated using the ultrasonic synthesis method, and hence, an extremely wide color gamut was obtained.

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... Colloidal quantum dots (QDs) have received extensive attention owing to their high photoluminescence quantum yield (PLQY), tunable emission wavelength, broad band absorption, and narrow emission band [1][2][3][4][5][6][7]. Due to its unique quantum confinement effect [7][8][9], researchers can achieve bandgap tuning by adjusting the emission color of QDs size and content [10,11]. Given these excellent optoelectronic properties, QDs are widely used in solar cells [12,13], light-emitting diodes (LEDs) [14,15], photodetectors [16,17], and lasers [18,19]. ...
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In this Perspective, the use of ultrasound in the synthesis and modification of carbon materials is surveyed. Ultrasound is a common laboratory tool used to nebulize solutions into fine mists, emulsify mixtures, and drive chemical reactions. Given society's continued use of carbon materials (e.g., carbon black and activated carbon) as pigments, adsorbents, and composite components as well as the exciting new applications being explored for carbon nanotubes, graphene, and meso- and macroporous carbons, the use of ultrasound in the synthesis and modification of carbon materials is of general interest. Here, carbon materials prepared by both ultrasonic spray pyrolysis and high intensity ultrasound will be discussed, with the properties and applications enabled by their preparation highlighted within the individual examples. This article is concluded with some personal perspectives on the directions toward which future research may be aimed.
Brightly luminescent and color-Tunable colloidal CH3NH3PbX3 (X = Br, I, Cl) quantum dots: potential alternatives for display technology
  • F Zhang
  • H Zhong
  • C Chen
  • X Wu
  • X Hu
  • H Huang
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