Liu Jiaqin, Li Jingwei, Dai Mengjia, Hu Ying, Cui Jiewu, Wang Yan, Tan Hark Hoe, Wu Yucheng
Institute of Industry and Equipment Technology, Hefei University of Technology Hefei 230009 China
Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei 230009 China
RSC Adv. 2018 Apr 10;8(24):13393-13400. doi: 10.1039/c7ra13166f. eCollection 2018 Apr 9.
An organic-inorganic coaxial-structured hybrid of PPy/EH-TNTAs electrode with outstanding supercapacitive performance was developed by incorporating electroactive polypyrrole (PPy) into a highly-conductive TiO substrate, namely, electrochemically hydrogenated TiO nanotube arrays (EH-TNTAs) through a photo-assisted potentiodynamic electrodeposition route. The as-fabricated PPy/EH-TNTAs hybrid electrode achieves a specific capacitance of up to 614.7 F g at 1.0 A g with 87.4% of the initial capacitance remaining after 5000 cycles at 10 A g, outperforming other fabricated PPy-TNTAs hybrid electrodes. The photoelectrodeposited and electrodeposited hybrid samples as well as the EH-TNTAs-based and air-TNTAs-based hybrid samples were fully compared from electropolymerization process, morphology, structural feature and electrochemical perspectives. The results indicate that the synergy of remarkably improved conductivity and electrochemical properties of the TiO substrate induced by intentionally introduced Ti (O-vacancies) as well as the homogenous and integrated deposition of PPy triggered by light illumination enabled the outstanding supercapacitive performance of the PPy/EH-TNTAs hybrid electrode. A symmetric supercapacitor device was assembled using the PPy/EH-TNTAs hybrid as both a positive and negative electrode, respectively. It displays a high energy density of 17.7 W h kg at a power density of 1257 W kg. This organic-inorganic coaxial-structured PPy/EH-TNTAs electrode will be a competitive and promising candidate for application in future energy storage devices.
通过光辅助恒电位电沉积法将电活性聚吡咯（PPy）引入高导电性TiO基底，即电化学氢化TiO纳米管阵列（EH-TNTAs）中，制备出了具有优异超级电容性能的PPy/EH-TNTAs有机-无机同轴结构混合电极。所制备的PPy/EH-TNTAs混合电极在1.0 A g时的比电容高达614.7 F g，在10 A g下循环5000次后仍保留87.4%的初始电容，性能优于其他制备的PPy-TNTAs混合电极。从电聚合过程、形貌、结构特征和电化学等角度对光沉积和电沉积的混合样品以及基于EH-TNTAs和基于空气-TNTAs的混合样品进行了全面比较。结果表明，有意引入的Ti（氧空位）诱导TiO基底的导电性和电化学性能显著提高，以及光照引发的PPy均匀且完整的沉积，二者协同作用使得PPy/EH-TNTAs混合电极具有优异的超级电容性能。使用PPy/EH-TNTAs混合材料分别作为正负极组装了对称超级电容器器件。在功率密度为1257 W kg时，其能量密度高达17.7 W h kg。这种有机-无机同轴结构的PPy/EH-TNTAs电极将是未来储能器件应用中具有竞争力和前景的候选材料。
