Tunable Nitrogen-Doping of Sulfur Host Nanostructures for Stable and Shuttle-Free Room-Temperature Sodium–Sulfur Batteries
| Autor: | Zhi Wei Seh, Jianwei Xu, Carina Yi Jing Lim, Xian Yi Tan, Si Yin Tee, Dan-Thien Nguyen, Alex Yong Sheng Eng, Yong Wang, Man-Fai Ng |
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| Rok vydání: | 2021 |
| Předmět: |
inorganic chemicals
Nanostructure Materials science Carbonization Mechanical Engineering Doping chemistry.chemical_element Bioengineering 02 engineering and technology General Chemistry Conductivity 021001 nanoscience & nanotechnology Condensed Matter Physics Nitrogen Sulfur Chemical engineering chemistry Electrical resistivity and conductivity General Materials Science 0210 nano-technology Faraday efficiency |
| Zdroj: | Nano Letters. 21:5401-5408 |
| ISSN: | 1530-6992 1530-6984 |
| Popis: | Room-temperature sodium-sulfur batteries have potential in stationary applications, but challenges such as loss of active sulfur and low electrical conductivity must be solved. Nitrogen-doped nanocarbon host cathodes have been employed in metal-sulfur batteries: polar interactions mitigate the loss of sulfur, while the conductive nanostructure addresses the low conductivity. Nevertheless, these two properties run contrary to each other as greater nitrogen-doping of nanocarbon hosts is associated with lower conductivity. Herein, we investigate the polarity-conductivity dilemma to determine which of these properties have the stronger influence on cycling performance. Lower carbonization temperatures produce more pyridinic nitrogen and pyrrolic nitrogen, which from density functional theory calculations preferentially bind discharge products (Na2S and short-chain polysulfides). Despite its lower conductivity, the highly doped composite showed better Coulombic efficiency and stability, retaining a high capacity of 980 mAh g(S)-1 after 800 cycles. Our findings represent a paradigm shift where nitrogen-doping should be prioritized in designing shuttle-free, long-life sodium-sulfur batteries. |
| Databáze: | OpenAIRE |
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