Clathrates of Tetrel elements (Si, Ge, Sn) have attracted interest for their potential use in batteries and other applications. Sodium-filled silicon clathrates are conventionally synthesized through thermal decomposition of the Zintl precursor Na4Si4, but phase selectivity of the product is often difficult to achieve. Herein, we report the selective formation of the type I clathrate Na8Si46using electrochemical oxidation at 450 °C and 550 °C. A two-electrode cell design inspired by high-temperature sodium-sulfur batteries is employed, using Na4Si4as working electrode, Na
- Publication Date:
- NSF-PAR ID:
- 10303793
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 168
- Issue:
- 2
- Page Range or eLocation-ID:
- Article No. 020516
- ISSN:
- 0013-4651
- Publisher:
- The Electrochemical Society
- Sponsoring Org:
- National Science Foundation
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