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Both organohalide perovskites and colloidal quantum dots are attractive and promising materials for optoelectronic applications. Recent experiments have combined the two to create “quantum dot-in-perovskite” assemblies for highly efficient light emissions. In this work, we unravel photoexcitation dynamics at the interface between the perovskite and the quantum dot by means of first-principle non-adiabatic molecular dynamics simulations. We find that such assemblies adopt the type-I band structure and are free of defect states. The interfacial and the electronic structure are robust against the thermal fluctuations at 300K. The lowest excitation is predicted to be localized entirely on the quantum dot and the photoexcited charge transfer takes place in a picosecond timescale. The charge transfer dynamics of the photoexcited electron and hole exhibits a moderate asymmetry, which can be attributed to the differences in electronic coupling between the donor and the acceptor and the electron-phonon coupling. The ultrafast and balanced charge transfer dynamics endows the ‘dot-in-a-crystal’ devices with unprecedented performance, which could lead to important applications in photovoltaics, photocatalysis, and infrared light emissions.
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Composite Structures with Emissive Quantum Dots for Light Enhancement
Abstract Since their inception, quantum dots have proven to be advantageous for light management applications due to their high brightness and well‐controlled absorption, scattering, and emission properties. As quantum dots become commercially available at large scale, the need for robust, stable, and flexible optical components continues to drive the development of robust and flexible quantum dot composite materials. In this review, after a thorough introduction to quantum dots, discussion delves into methods for fabricating quantum dot loaded composite optical elements such as thin films, microfabricated patterns, and microstructures. The importance of surface chemistry and ligand engineering, host matrixes, wet processing, and unique patterning methodologies is presented by considering photostability, aggregation, and phase separation of quantum dots in corresponding composites. With regard to prospective optical applications of quantum dot materials, emphasis is placed on light emitting and guiding composite materials for lasing applications, specifically whispering gallery mode‐based photonic microsystems. These developments will enable novel flexible, portable, and miniaturized optoelectronic devices such as light‐emitting diodes, flexible pixelated displays, solar cells, large‐area microwaveguides, omnidirectional micromirrors, optical metasurfaces, and directional microlasers.
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- Award ID(s):
- 1803495
- PAR ID:
- 10462470
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 7
- Issue:
- 4
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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