Stable Cycling of Phosphorus Anode for Sodium‐Ion Batteries through Chemical Bonding with Sulfurized Polyacrylonitrile

Abstract

Sodium-ion batteries are attracting increasing interests as a promising alternative to lithium-ion batteries due to the abundant resource and low cost of sodium. Despite phosphorus (P) has extremely high theoretical capacity of 2595 mAh g −1 , its wide application for sodium-ion battery is highly hampered by its fast capacity fading and low Coulombic efficiency as a result of large volume change upon cycling. Herein, a robust phosphorus anode with long cycle life for sodium-ion battery via hybridization with functional conductive polymer is presented. To this end, the polyacrylonitrile is first dehydrogenated by sulfur via a facile thermal treatment, forming a conductive main chain embedded with C-S-S moieties. This functional conductive polymer enables the formation of PS bonds between phosphorus and functional conductive matrix, leading to a robust electrode that can accommodate the large volume change upon substantial volume change in cycling. Consequently, this hybrid anode delivers a high capacity of ≈1300 mAh g −1 at a current density of 520 mA g −1 with high Coulombic efficiency (>99%) and good cycling performance (91% capacity retention after 100 cycles).

Red Phosphorus/Onion‐like Mesoporous Carbon Composite as High‐Performance Anode for Sodium‐Ion Battery

“…Therefore, we can assume that the capacity contribution of carbon matrix in the composites is negligible, especially at high rate. The electrochemical performances of other reported P/C composites were given to compare with the P/OCNPs composite in the Table S1 . All the capacities are calculated based on the mass of red P. Our electrochemical performance is comparable with or better than the reported P/C anodes.…”

“…The electrochemical performances of other reported P/C composites were given to compare with the P/OCNPs composite in the Table S1. [13,17,20,[25][26][27][28][29][30][31][32] All the capacities are calculated based on the mass of red P. Our electrochemical performance is comparable with or better than the reported P/C anodes.…”

“…For phosphorus anode, the columbic efficiency of the first cycle is generally low, due to the formation of irreversible solidelectrolyte interfaces (SEI) layer. [25] Commercial red P microparticles only has an initial columbic efficiency of 5 % at 0.5 C. The columbic efficiency of P/OCNPs-1 in the first cycle is significantly improved to 83.3 %, and keeps stable at about 99.3 % throughout following cycles; P/OCNPs-2 has a high initial efficiency of 76.9 %, but fluctuates severely during the subse-quent cycles. These electrochemical performances strongly support our expectations that mesoporous onion-like carbon nanoparticles are effective in the promoting reversibility of (de) sodiation reaction of phosphorus and improving the cycling stability, due to the alleviated volume expansion and pulverization of active phosphorus.…”

“…For phosphorus anode, the columbic efficiency of the first cycle is generally low, due to the formation of irreversible solid‐electrolyte interfaces (SEI) layer . Commercial red P microparticles only has an initial columbic efficiency of 5 % at 0.5 C. The columbic efficiency of P/OCNPs‐1 in the first cycle is significantly improved to 83.3 %, and keeps stable at about 99.3 % throughout following cycles; P/OCNPs‐2 has a high initial efficiency of 76.9 %, but fluctuates severely during the subsequent cycles.…”

Recent Progress in Multivalent Metal (Mg, Zn, Ca, and Al) and Metal‐Ion Rechargeable Batteries with Organic Materials as Promising Electrodes

“…To gain insight into these issues, effective approaches are encouraged to be proposed to improve the current situation of organic‐electrode‐based multivalent metal and metal‐ion batteries. Actually, recent successful strategies from organic lithium (Li)‐ion batteries based on conductive polymers, conjugated polymers, carbonyl compounds,[37a,41‐48] and new redox chemistry compounds afford us sufficient experiences that merit attention. Innovative demonstrations including all‐organic‐electrode and all‐solid‐state batteries have also been realized based on these materials .…”