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Abstract Motivated by the high-performance solid-state lithium batteries enabled by lithium superionic conductors, sodium superionic conductor materials have great potential to empower sodium batteries with high energy, low cost, and sustainability. A critical challenge lies in designing and discovering sodium superionic conductors with high ionic conductivities to enable the development of solid-state sodium batteries. Here, by studying the structures and diffusion mechanisms of Li-ion versus Na-ion conducting solids, we reveal the structural feature of face-sharing high-coordination sites for fast sodium-ion conductors. By applying this feature as a design principle, we discover a number of Na-ion conductors in oxides, sulfides, and halides. Notably, we discover a chloride-based family of Na-ion conductors NaxMyCl6(M = La–Sm) with UCl3-type structure and experimentally validate with the highest reported ionic conductivity. Our findings not only pave the way for the future development of sodium-ion conductors for sodium batteries, but also consolidate design principles of fast ion-conducting materials for a variety of energy applications.
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Stretchable 3D lattice conductors
3D architectures have been long harnessed to create lightweight yet strong cellular materials; however, the study regarding how 3D architectures facilitate the design of soft materials is at the incipient stage. Here, we demonstrate that 3D architectures can greatly facilitate the design of an intrinsically stretchable lattice conductor. We show that 3D architectures can be harnessed to enhance the overall stretchability of the soft conductors, reduce the effective density, enable resistive sensing of the large deformation of curved solids, and improve monitoring of a wastewater stream. Theoretical models are developed to understand the mechanical and conductive behaviors of the lattice conductor. We expect this type of lattice conductors can potentially inspire various designs of 3D-architected electronics for diverse applications from healthcare devices to soft robotics.
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- Award ID(s):
- 1649093
- PAR ID:
- 10080521
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 13
- Issue:
- 42
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 7731 to 7739
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c7sm01435j
