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Metal halide perovskites and their nanostructures have efficient optical absorption and emission in the visible range with high external quantum efficiency. They have been at the forefront of next-generation photovoltaics and optoelectronics applications. But several intrinsic limitations of perovskites including low stability and incompatibility with lithography-based patterning constrains their broader applications. In recent years, the integration of perovskites with polymers especially multifunctional block copolymers (BCPs) has provided a new approach to overcome those issues. The chemical composition and chain architecture of BCPs are critical for achieving synergistic effects with perovskites in their hybrid systems. In this Highlight review article, we provide an overview and critical summary of the recent progress in the creation of perovskite–BCP hybrid structures, with a focus on the different roles of BCPs. The major categories include: (i) BCPs act as the nanopattern template for the spatial control and patterning of perovskite; (ii) BCP micelles or stars act as the template for perovskite nanostructure crystallization; (iii) BCPs act as the macromolecular ligands for perovskite NCs during its solution synthesis; (iv) BCP encapsulation of perovskite NCs into hierarchical composite particles; and (v) BCP incorporation into bulk perovskite and forming bulk composite films. The applications of perovskite–BCP hybrid structures in various fields and the major current challenges are also identified and discussed.
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Designed Polymer Ligands for Perovskite Quantum Dots and Their Block Copolymer Nanocomposites
Abstract Perovskite quantum dots (QDs) have efficient optical absorption and emission in the visible range, and show a strong quantum confinement effect and high external quantum efficiency. They have been at the forefront of next‐generation photovoltaics and optoelectronics applications. However, two major challenges associated with perovskites and their nanomaterials are poor stability (such as against moisture and polar solvents), as well as the lack of efficient nanopatterning methods. In this work, a promising approach is provided to address both of those major challenges by molecular engineering and integration of QDs with block copolymers (BCP). The BCP thermoplastic elastomers not only substantially improve the stability of perovskite QDs by encapsulating them in a highly stable and soft matrix, but also enable molecular‐level control of the alignment and assembly of perovskite QDs in the microphase‐separated BCP matrix. It is demonstrated that designing and synthesis of compatible polymer ligands for perovskite QDs is key to enabling their selective and strong interaction with the BCP matrix. The structure and molecular weight of the BCP also play an important role in the interfacial structure and optical properties of the QDs‐BCP nanocomposites. Such soft and flexible optical nanocomposites have potential applications in flexible optoelectronics, optical storage, and displays.
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- Award ID(s):
- 2213054
- PAR ID:
- 10480145
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 12
- Issue:
- 13
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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