J. Mater. Sci. Technol. ›› 2021, Vol. 76: 11-19.DOI: 10.1016/j.jmst.2020.11.014

• Research Article • Previous Articles     Next Articles

Experimental design and theoretical evaluation of nitrogen and phosphorus dual-doped hierarchical porous carbon for high-performance sodium-ion storage

Chen Chena, Ying Huanga,*(), Zhuoyue Mengb, Mengwei Lua, Zhipeng Xua, Panbo Liua, Tiehu Lic   

  1. a MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an, 710072, China
    b College of Chemistry & Chemical Engineering, Xi’an University of Science and Technology, Xi’an, 710072, China
    c Shaanxi Joint Laboratory of Graphene, Northwestern Polytechnical University, Xi’an, 710072, China
  • Received:2020-07-01 Revised:2020-09-10 Accepted:2020-10-04 Published:2021-06-20 Online:2020-11-07
  • Contact: Ying Huang
  • About author:*E-mail address: yingh@nwpu.edu.cn (Y. Huang).

Abstract:

Starch has a wide range of sources and can be used as a high-quality precursor for sodium-ion battery anode materials. However, the carbonization yield and specific capacity of carbon materials obtained by directly pyrolyzing starch are low. Herein, starch is used as the carbon source, and ammonium polyphosphate (APP) is used as the cross-linking agent and dopant to prepare a nitrogen and phosphorus co-doped porous carbon (NPPC). As the anode for sodium-ion batteries, NPPC-2 exhibits a high reversible capacity of 385.8 mA h g-1 at 50 mA g-1. Even after 1000 cycles at a large current density of 5 A g-1, the reversible capacity can still be maintained at 126.9 mA h g-1. Based on detailed data and first-principles calculations, the excellent performance of NPPC is due to the effective doping of nitrogen and phosphorus elements, which distorts the graphite sheet, introduces defects, and increases the graphite layer spacing, thereby enhancing the adsorption capacity of the carbon material for sodium ions, reducing the diffusion barrier of sodium ions. This work provides a new idea for heteroatom doping and carbon material modification.

Key words: Ammonium polyphosphate, Starch, N,P co-doped, Anode, Sodium-ion battery