Si‐based anodes with a stiff diamond structure usually suffer from sluggish lithiation/delithiation reaction due to low Li‐ion and electronic conductivity. Here, a novel ternary compound ZnSi2P3with a cation‐disordered sphalerite structure, prepared by a facile mechanochemical method, is reported, demonstrating faster Li‐ion and electron transport and greater tolerance to volume change during cycling than the existing Si‐based anodes. A composite electrode consisting of ZnSi2P3and carbon achieves a high initial Coulombic efficiency (92%) and excellent rate capability (950 mAh g−1at 10 A g−1) while maintaining superior cycling stability (1955 mAh g−1after 500 cycles at 300 mA g−1), surpassing the performance of most Si‐ and P‐based anodes ever reported. The remarkable electrochemical performance is attributed to the sphalerite structure that allows fast ion and electron transport and the reversible Li‐storage mechanism involving intercalation and conversion reactions. Moreover, the cation‐disordered sphalerite structure is flexible to ionic substitutions, allowing extension to a family of Zn(Cu)Si2+
Herein, the synthesis of Cu3(HAB)x(TATHB)2‐x(HAB: hexaaminobenzene, TATHB: triaminotrihydroxybenzene) is reported. Synthetic improvement of Cu3(TATHB)2leads to a more crystalline framework with higher electrical conductivity value than previously reported. The improved crystallinity and analogous structure between TATHB and HAB enable the synthesis of Cu3(HAB)x(TATHB)2‐xwith ligand compositions precisely controlled by precursor ratios. The electrical conductivity is tuned from 4.2 × 10−8to 2.9 × 10−5 S cm−1by simply increasing the nitrogen content in the crystal lattice. Furthermore, computational calculation supports that the solid solution facilitates the band structure tuning. It is envisioned that the findings not only shed light on the ligand‐dependent structure–property relationship but create new prospects in synthesizing multicomponent electrically conductive metal‐organic frameworks (MOFs) for tailoring optoelectronic device applications.
more » « less- Award ID(s):
- 2145209
- NSF-PAR ID:
- 10391430
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 19
- Issue:
- 11
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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