Nitrogen-doped porous graphene/MnO2 composite as sulfur hosts for lithium-sulfur batteries
| Autor: | Yongpeng Li, Xiaoming Zhu, Chenwei Li, Xiangtao Yu, Ziyuan Pei, Zhuyin Sui |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Materials science
Graphene Mechanical Engineering Composite number chemistry.chemical_element Nanoparticle Aerogel 02 engineering and technology General Chemistry Manganese 010402 general chemistry 021001 nanoscience & nanotechnology Electrochemistry 01 natural sciences Sulfur Cathode 0104 chemical sciences Electronic Optical and Magnetic Materials law.invention chemistry Chemical engineering law Materials Chemistry Electrical and Electronic Engineering 0210 nano-technology |
| Zdroj: | Diamond and Related Materials. 118:108497 |
| ISSN: | 0925-9635 |
| Popis: | Lithium‑sulfur batteries have been considered as a promising chemical power source owing to the low costs, high energy densities, and nontoxicity. However, sulfur-based cathodes have several shortcomings, including poor electrochemical activity and fast capacity attenuation. In this work, manganese dioxide (MnO2) and nitrogen-doped porous graphene (pNGA) were introduced to the sulfur cathode to improve its electrochemical activity and prevent the rapid decay of capacity. The pNGA/MnO2 composite with a three-dimensional architecture was fabricated by steam etching of nitrogen-doped graphene aerogel and chemical deposition of MnO2 nanoparticles. In this structure, the nitrogen-doped porous graphene acts as a skeleton to form a conductive network. The MnO2 particles anchored on graphene sheets have a good interaction with polysulfides. The as-prepared pNGA/MnO2@S cathode shows an excellent comprehensive electrochemical performance. The calculated specific capacities are 1144, 1007, 920, 852, and 762 mA h g−1 at 0.1C, 0.2C, 0.5C, 1C, and 2C respectively. In addition, the pNGA/MnO2@S cathode displays a good cycling performance: the specific capacity maintains at 887 mA h g−1 at 0.5C over 100 cycles. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect