Wang Peng, Zhang Yifu, Feng Ziyi, Liu Yanyan, Meng Changgong
State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
J Colloid Interface Sci. 2022 Jan 15;606(Pt 2):1322-1332. doi: 10.1016/j.jcis.2021.08.036. Epub 2021 Aug 9.
Recently, aqueous rechargeable batteries employing ammonium-ions (NH) as charge carriers have received increasing interest because of their merits of eco-friendly, low cost and sustainability. However, the supercapacitor based on NH charge carriers has rarely been reported probably owing to the lack of a suitable system to achieve acceptable capacitance and cycle performance for NH storage. Herein, we develop a dual-polymer strategy to boost the electrochemical properties of hydrated vanadium oxide (HVO) for outstanding NH storages based on a supercapacitor. One polymer polyaniline (PANI) is intercalated into the interlayer space of HVO (11.0 Å) to synthesize PANI-intercalation-HVO (PVO) with the expanded interlamellar spacing of 13.9 Å, which enhances the kinetics and stabilizes the structure during the NH (de)intercalation. The capacitance at 1 A·g is significantly improved from 156F·g (HVO) to 351F·g (PVO). The other polymer polyvinyl alcohol (PVA) is used to get the quasi-solid-state (QSS) PVA/NHCl electrolyte, in which the cycle stability of PVO electrode is effectively improved. The PVO exhibits the capacitance retentions of 82% after 2000 cycles and 56% after 10,000 cycles, whereas this value is only 29% after 3000 cycles in NHCl electrolyte. The findings reveal that this strategy can effectively reduce the diffusion resistance of ammonium ions and improve the energy storage efficiency of PVO. The flexible QSS PVO//active carbon hybrid supercapacitor (FQSS PVO//AC HSC) device is assembled and exhibits outstanding capacitance, long cycle stability, good mechanical stability and potential practical applications. This work may open up a new window for the study on the improved electrochemical properties of electrode materials for NH storage.
最近，采用铵离子（NH）作为电荷载体的水系可充电电池因其环保、低成本和可持续性等优点而受到越来越多的关注。然而，基于NH电荷载体的超级电容器鲜有报道，这可能是由于缺乏一个合适的体系来实现可接受的NH存储电容和循环性能。在此，我们开发了一种双聚合物策略，以提高水合氧化钒（HVO）的电化学性能，用于基于超级电容器的优异NH存储。一种聚合物聚苯胺（PANI）插入到HVO（11.0 Å）的层间空间中，合成层间距扩大到13.9 Å的聚苯胺插层HVO（PVO），这增强了动力学并在NH嵌入/脱嵌过程中稳定了结构。1 A·g时的电容从156F·g（HVO）显著提高到351F·g（PVO）。另一种聚合物聚乙烯醇（PVA）用于制备准固态（QSS）PVA/NHCl电解质，其中PVO电极的循环稳定性得到有效提高。PVO在2000次循环后电容保持率为82%，在10000次循环后为56%，而在NHCl电解质中3000次循环后该值仅为29%。研究结果表明，该策略可以有效降低铵离子的扩散电阻，提高PVO的储能效率。组装了柔性QSS PVO//活性炭混合超级电容器（FQSS PVO//AC HSC）器件，该器件具有出色的电容、长循环稳定性、良好的机械稳定性和潜在的实际应用价值。这项工作可能为研究用于NH存储的电极材料的改进电化学性能打开一扇新窗口。
