Interfacial Self-assembly of Organics/MXene Hybrid Cathodes Toward High-Rate-Performance Sodium Ion Batteries
Yijun Gao, Ping Xue, Lijun Ji, Xin Pan, Lining Chen, Wei Guo, Mi Tang, Chengliang Wang, Zhengbang Wang
Abstract
Conjugated quinones are promising cathode materials for sodium-ion batteries. However, the contemporary primary conjugated quinones cathodes still hold to limited capacity, poor rate performance and low cyclability, due to the poor electronic and ionic conductivity. Herein, a series of high-performance conjugated-quinones@MXene hybrid cathodes is constructed by an in situ polymerization-assembly strategy based on the hydrogen bond and S–Ti interaction. The PAQS@Ti3C2Tx MXene hybrid, as a typical example, exhibits sandwiched structure with intimate PAQS@MXene contact, resulting in efficient interfacial mass transfer. The assembled MXene is able to build interconnected conductive channels in the hybrid cathodes for continuous and fast electrons/ions transport, which is verified by both the experimental results and density functional theory (DFT) calculations. As a result, the optimal PAQS@MXene hybrid electrode delivers excellent electrochemical performances with high capacity (∼242 mA h g–1 at 100 mA g–1), superior fast-charge/discharge ability (∼148 and 121 mA h g–1 at 5 and 10 A g–1, respectively), and ultralong cycle life (capacity as high as 57 mA h g–1 after 9000 cycles at 5 A g–1), which are more superior to that of the pure PAQS electrodes. Besides, the analogous PPTS@Ti3C2Tx MXene hybrid cathode also shows better performances compared to the pure materials.