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Hybrid lead-halide perovskites have been studied extensively for their promising optoelectronic properties and prospective applications including photovoltaics, solid-state lighting, and radiation detection. Research into these materials has also been aided by the simple and low temperature synthetic conditions involved in solution-state deposition/crystallization or melt processing techniques. However, concern over lead toxicity has plagued the field since its early days. One of the most promising routes to mitigating toxicity in hybrid perovskite materials is substituting isoelectronic Bi(III) for Pb(II). Various methods have been developed to allow pnictide-based systems to capture properties of the Pb(II) analogs, but the ability to melt process extended hybrid pnictide-halide materials has not been investigated. In this work, we prepare a series of 1D antimony and bismuth-iodide hybrid materials employing tetramethylpiperazinium (TMPZ)-related cations. We observe, for the first time, the ability to melt hybrid pnictide-halide materials for both Sb(III) and Bi(III) systems. Additionally, we find that Sb(III) analogs melt at lower temperatures, and attribute this observation to structural changes induced by the increased stereochemical activity of the Sb(III) lone pair coupled with reduction in effective dimensionality due to steric interactions with the organic cations. Finally, we demonstrate the ability to melt process phase pure thin films of (S-MeTMPZ)SbI5.
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Rudorffites and Beyond: Perovskite‐Inspired Silver/Copper Pnictohalides for Next‐Generation Environmentally Friendly Photovoltaics and Optoelectronics
Abstract In the wake of lead‐halide perovskite research, bismuth‐ and antimony‐based perovskite‐inspired semiconducting materials are attracting increasing attention as safer and potentially more robust alternatives to lead‐based archetypes. Of particular interest are the group IB–group VA halide compositions with a generic formula AxByXx+3y(A+ = Cu+/Ag+; B3+ = Bi3+/Sb3+; X– = I–/Br–), i.e., silver/copper pnictohalides and derivatives thereof. This family of materials forms 3D structures with much higher solar cell efficiencies and greater potential for indoor photovoltaics than the lower‐dimensional bismuth/antimony‐based perovskite‐inspired semiconductors. Furthermore, silver/copper pnictohalides are being investigated for applications beyond photovoltaics, e.g., for photodetection, ionization radiation detection, memristors, and chemical sensors. Such versatility parallels the wide range of possible compositions and synthetic routes, which enable various structural, morphological, and optoelectronic properties. This manuscript surveys the growing research on silver/copper pnictohalides, highlighting their composition–structure–property relationships and the status and prospects of the photovoltaic and optoelectronic devices based thereon. The authors hope that the insights provided herein might accelerate the development of eco‐friendly and stable perovskite‐inspired materials for next‐generation photovoltaics and optoelectronics.
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- Award ID(s):
- 2127473
- PAR ID:
- 10371127
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 32
- Issue:
- 36
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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