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Abstract Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid‐state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two‐dimensional Sr(Ag1−xLix)2Se2layered phases. With increased LiOH/LiCl ratio or reaction temperature, Li partially substituted Ag to form solid solutions of Sr(Ag1−xLix)2Se2withxup to 0.45. In addition, a new type of intergrowth compound [Sr3Se2][(Ag1−xLix)2Se2] was synthesized upon further reaction of Sr(Ag1−xLix)2Se2with SrSe. Both Sr(Ag1−xLix)2Se2and [Sr3Se2][(Ag1−xLix)2Se2] exhibit a direct band gap, which increases with increasing Li substitution (x). Therefore, the band gap of Sr(Ag1−xLix)2Se2can be precisely tuned via fine‐tuningxthat is controlled by only the flux ratio and temperature.
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On the structure of heptalithium distannide: Li7Sn2 or Li7−xSn2 (0.3 x < 0.5)
New structural insights into Li7−xSn2reveal partial/vacant Li occupancy.
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- Award ID(s):
- 2004514
- PAR ID:
- 10644506
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 54
- Issue:
- 34
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 12859 to 12867
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/D5DT01022E
