PEDOT Nanowires Connecting Exfoliated HNb<sub>3</sub>O<sub>8</sub> Nanosheets as High-Rate Anode for Lithium-Ion Capacitor
Yu Zhang, Zhiyuan Yu, Xianchi Zhang, Xuexia He, Qi Li, Jie Sun, Liqin Dang, Zong‐Huai Liu, Zhibin Lei
Abstract
The development of anode materials with fast ion and electron kinetics is of great significance for a high-performance lithium-ion capacitor. In this work, we reported the incorporation of conductive poly(3,4-ethlenedioxythiophene) (PEDOT) nanowires between the exfoliated HNb 3 O 8 (E-HNb 3 O 8 ) to prepare the E-HNb 3 O 8 -PEDOT composite electrodes for lithium-ion capacitor. The conductive PEDOT nanowires in the E-HNb 3 O 8 -PEDOT composite inhibit the restacking of E-HNb 3 O 8 sheets, create numerous ion pathways, and significantly enhance the electrode conductivity. Benefiting from the favorable ion and electron pathways, the E-HNb 3 O 8 -PEDOT composite electrode demonstrates substantially enhanced performance, including high discharge capacity (540 mAh g –1 at 0.1 A g –1 ), high rate capability (174 mAh g –1 at 10 A g –1 ), and good cycling lifespan (65.4% capacity retention at 10 A g –1 for 1000 cycles). The lithium-ion capacitor assembled with E-HNb 3 O 8 -PEDOT and activated carbon can deliver a maximum energy density of 80 Wh kg –1 . Meanwhile, it maintains about 83% capacity and almost 98% Coulombic efficiency after 1000 cycles at 1.0 A g –1 . Our results indicate that the PEDOT nanowires are promising building blocks for constructing kinetically favorable ion and electron pathways for rapid lithium-ion storage.