Enhanced Ionic/Electronic Transport in Nano‐TiO 2 /Sheared CNT Composite Electrode for Na + Insertion‐based Hybrid Ion‐Capacitors
Enhanced Ionic/Electronic Transport in Nano‐TiO 2 /Sheared CNT Composite Electrode for Na + Insertion‐based Hybrid Ion‐Capacitors
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用于 Na 插入混合离子电容器的纳米 TiO 2 /剪切 CNT 复合电极中增强的离子/电子传输
DOI：
10.1002/adfm.201908309
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发表时间：
2020
影响因子：
19
通讯作者：
Shiyou Zheng
中科院分区：
文献类型：
--
作者：
Sainan Luo;Tao Yuan;Luke Soule;Jiafeng Ruan;Yahui Zhao;Dalin Sun;Junhe Yang;Meilin Liu;Shiyou Zheng
离子插入电容器有望弥合高功率密度超级电容器和高能量密度电池之间的差距。虽然研究工作主要集中在Li+基电容器（lic）上，但Na+基电容器（sic）理论上更便宜，更具可持续性。由于Na+比Li+的尺寸更大，寻找高速率的sic阳极材料一直具有挑战性。本文报道了一种SIC阳极结构，由固定在剪切碳纳米管骨架（TiO2/SCNT）上的TiO2纳米颗粒组成。SCNT结构比其他常用的碳结构（如还原氧化石墨烯和碳纳米管）具有优势。在半电池中，TiO2/SCNT电极在1℃充放电速率下的容量为267 mAh g - 1，在10℃充放电速率下的容量为136 mAh g - 1，在1000次循环中保持87%的初始容量。当在一个完整的电池中与活性炭（AC）结合时，能量密度和功率密度分别达到54.9 Wh kg - 1和1410 W kg - 1，同时在5000次循环中保持90%的容量保持。TiO2/SCNT结构的电子导电性和Na+导电性增强，使电极具有良好的速率性能、能量和功率密度以及耐用性。
Ion‐insertion capacitors show promise to bridge the gap between supercapacitors of high power densities and batteries of high energy densities. While research efforts have primarily focused on Li+‐based capacitors (LICs), Na+‐based capacitors (SICs) are theoretically cheaper and more sustainable. Owing to the larger size of Na+compared to Li+, finding high‐rate anode materials for SICs has been challenging. Herein, an SIC anode architecture is reported consisting of TiO2nanoparticles anchored on a sheared‐carbon nanotubes backbone (TiO2/SCNT). The SCNT architecture provides advantages over other carbon architectures commonly used, such as reduced graphene oxide and CNT. In a half‐cell, the TiO2/SCNT electrode shows a capacity of 267 mAh g−1at a 1 C charge/discharge rate and a capacity of 136 mAh g−1at 10 C while maintaining 87% of initial capacity over 1000 cycles. When combined with activated carbon (AC) in a full cell, an energy density and power density of 54.9 Wh kg−1and 1410 W kg−1, respectively, are achieved while retaining a 90% capacity retention over 5000 cycles. The favorable rate capability, energy and power density, and durability of the electrode is attributed to the enhanced electronic and Na+conductivity of the TiO2/SCNT architecture.