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Title: Mixed-Metal Alloying in Hybrid Bronzes
We show that substitutional alloying during the aqueous self-assembly of layered organic-templated metal oxides produces single-phase mixed-metal hybrids. Single-crystal X-ray diffraction, bulk elemental analyses, and vibrational and electronic spectroscopies corroborate a solid solution of Mo and W atoms at lattice sites within the two-dimensional metal oxide layers. Mild postsynthetic reduction then introduces relatively delocalized electrons to afford mixed-metal hybrid bronzes. To our knowledge, this represents the first demonstration of mixed-metal alloying in a hybrid metal oxide and a rare example of solid-solution formation at low temperature. We show this approach yields mixed-metal congeners with optical band gaps over 130 meV smaller than those of single-metal analogs, while achieving activation energies (Ea) of conduction as low as 78.4(2) meV. Further, metal substitution appears to tune collective electronic phenomena by suppressing the non-Arrhenius behavior observed for Mo-based hybrids. This work considerably expands the nascent hybrid bronze platform to help address energy-related challenges and fundamental solid-state physical questions.  more » « less
Award ID(s):
2338086
PAR ID:
10542180
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Journal of the American Chemical Society
Date Published:
Journal Name:
Journal of the American Chemical Society
ISSN:
1520-5126
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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