Yuan Yue, Wang Chenchen, Lei Kaixiang, Li Haixia, Li Fujun, Chen Jun
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin 300071, P. R. China.
ACS Cent Sci. 2018 Sep 26;4(9):1261-1265. doi: 10.1021/acscentsci.8b00437. Epub 2018 Aug 31.
Sodium-ion hybrid capacitors (NHCs) have been attracting research interest in recent years. However, NHCs suffer from slower redox reaction kinetics of electrodes as compared to non-Faradaic capacitive counterparts. Herein, a high-performance NHC using porous NaBi as anode, activated carbon (AC) as cathode, and 1.5 M of NaPF in diglyme as electrolyte is reported. In a charging process, Na is inserted into NaBi to form NaBi, and PF is stored in the electric double layers of the AC cathode; in a reverse process, the NaBi is desodiated to NaBi and eventually Bi, and the adsorbed PF is released into the electrolyte in the first cycle. The NHC exhibits a capacity of ∼298 mA h g , capacity retention of 98.6% after 1000 cycles at 2 A g , and Coulombic efficiency of >99.4%. The achievable power and energy density are as high as 11.1 kW kg and 106.5 W h kg , respectively. The superior electrochemical performance is ascribed to the gradually formed three-dimensional (3D) porous and stable networks of the anode, ensuring its comparable fast reaction kinetics and cycle stability to the AC cathode.
近年来，钠离子混合电容器（NHCs）一直吸引着研究兴趣。然而，与非法拉第电容同类产品相比，NHCs的电极氧化还原反应动力学较慢。在此，报道了一种高性能NHC，其使用多孔NaBi作为阳极，活性炭（AC）作为阴极，以及1.5 M的NaPF在二甘醇二甲醚中作为电解质。在充电过程中，Na插入到NaBi中形成NaBi，并且PF存储在AC阴极的双电层中；在反向过程中，NaBi去钠化为NaBi并最终变为Bi，并且在第一个循环中吸附的PF释放到电解质中。该NHC表现出约298 mA h g的容量，在2 A g下1000次循环后的容量保持率为98.6%，库仑效率大于99.4%。可实现的功率和能量密度分别高达11.1 kW kg和106.5 W h kg。优异的电化学性能归因于阳极逐渐形成的三维（3D）多孔且稳定的网络，确保其与AC阴极具有相当的快速反应动力学和循环稳定性。
