Enhanced Na pseudocapacitance in a P, S co-doped carbon anode arising from the surface modification by sulfur and phosphorus with C-S-P coupling

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2020-01, Vol.8 (1), p.422-432
• Main Authors: Yan, Jie, Li, Wei, Feng, Pingyuan, Wang, Ruxing, Jiang, Mao, Han, Jing, Cao, Shengling, Wang, Kangli, Jiang, Kai
• Format: Article
• Language: English
• Subjects: Anodes; Atomic properties; Batteries; Carbon; Carbon disulfide; Charge transfer; Chemical bonds; Doping; Immobilization; Interlayers; Phosphorus; Sodium; Sodium-ion batteries; Sulfur; Vacuum
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c9ta11594c

Enhanced phosphorus (7.2 wt%) and sulfur (15.7 wt%) co-doped carbon (PSC) is synthesized via a one-step sintering of carbon disulfide and red phosphorus in a vacuum. It is found that S atoms can act as immobilization sites for phosphorus by covalently bonding with P atoms in the form of C-S-P, and thus high-level doping of phosphorus can be realized. Owing to the high-level doping, this co-doped carbon shows enlarged interlayer spacing, improved charge transfer capability and strong adsorption of Na + ions. When tested as an anode for sodium ion batteries, this PSC delivers a high reversible capacity of 513.8 mA h g −1 at 100 mA g −1 , excellent rate capability of 181.8 mA h g −1 at 10 A g −1 and superior cycling stability with a capacity of 290.1 mA h g −1 after 1000 cycles at 1 A g −1 . Enhanced phosphorus (7.2 wt%) and sulfur (15.7 wt%) co-doped carbon (PSC) is synthesized via a one-step sintering of carbon disulfide and red phosphorus in a vacuum.