Inorganic halide perovskites (IHPs) have recently attracted huge attention in the field of optoelectronics. IHPs are generally expected to exhibit superior chemical stability over the prevailing hybrid organic–inorganic perovskites that are widely used in optoelectronic devices such as solar cells and light-emitting devices. This is primarily owing to the elimination of weakly-bonded organic components in the IHP crystal structure. Nevertheless, many recent studies have revealed that IHPs still suffer significant issues in chemical instability, and thus, a lot of effort has been made towards the stabilization of IHPs for high-performance devices. In this context, a great deal of interest in the chemistry and perovskite community has been emerging to understand the chemical (in)stability of IHPs and develop engineering strategies for making more robust perovskite devices. This review will summarize the past research progress in this direction, give insights into the IHP (in)stability, and provide perspectives for the future effort in making stable IHP materials and devices.
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Two-dimensional halide perovskites featuring semiconducting organic building blocks
Two-dimensional (2D) organic–inorganic hybrid halide perovskites exhibit unique properties, such as long charge carrier lifetimes, high photoluminescence quantum efficiencies, and great tolerance to defects. Over the last several decades tremendous progress has occurred in the development of 2D layered halide perovskite semiconductor materials and devices. Chemical functionalization of 2D halide perovskites is an effective approach for tuning their electronic properties. A large amount of effort has been made in compositional engineering of the cations and anions in the perovskite lattice. However, few efforts have incorporated rationally designed semiconducting organic moieties into these systems to alter the overall chemical and optoelectronic properties of 2D perovskites. In fact, incorporation of large conjugated organic groups in the spatially confined inorganic perovskite matrix was found to be challenging, and this synthetic challenge hinders a deeper understanding of the materials’ structure–property relationships. Recently, exciting progress has been made regarding the molecular design, optical characterization, and device fabrication of novel 2D halide perovskite materials that incorporate functional organic semiconducting building blocks. In this article, we provide a timely review regarding this recent progress. Moreover, we discuss successes and current challenges regarding the synthesis, characterization, and device applications of such hybrid materials and provide a perspective on the true future promise of these advanced nanomaterials.
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- Award ID(s):
- 1939986
- PAR ID:
- 10191193
- Date Published:
- Journal Name:
- Materials Chemistry Frontiers
- ISSN:
- 2052-1537
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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