柔性基金属氧化物超级电容器电极材料的研究进展

作为一种介于传统电容器和电池之间的新型电化学储能器件,超级电容器的整体性能主要受限于电极材料。研究发现,具有赝电容特性的过渡金属氧化物因其多重氧化态、多金属离子特性和高理论比容量,在电化学储能相关领域备受关注。首先简要阐述了柔性超级电容器的结构及储能机理。然后,概述了以不同元数的过渡金属氧化物为主体构筑的"二元"和"三元"柔性复合电极材料。接着,总结了由复合电极材料组装成的柔性超级电容器在可穿戴电子设备和多功能柔性器件——储能智能窗(ESS窗)方面的应用。最后,提出了过渡金属氧化物基柔性超级电容器在实际应用中所面临的挑战及今后的主要研究方向。     

柔性超级电容器电极材料制备方法研究进展

随着柔性超级电容器在可穿戴、小型化、便携式、柔性消费电子产品中的潜在应用,新材料、新加工技术和新设计得到了推广。电极材料是柔性超级电容器中重要的组成部分,其优异的性能决定了整个器件的应用。通过介绍柔性超级电容器电极材料的制备方法,总结了柔性超级电容器现阶段发展所面临的挑战,期望为制备高性能的柔性超级电容器提供参考。     

静电纺柔性超级电容器电极材料的研究进展

柔性超级电容器具有充放电速度快、功率密度高和能量密度高等优点,已成为智能可穿戴设备的理想供能器件。其中,优异的电化学性能和良好的柔韧性是供能器件追求的关键性能指标,而电极材料是其中的核心部分。电极材料的制备方法有沉积法、纺丝法、喷涂法、涂覆法和3D打印等,其中,纺丝法中的静电纺丝技术工艺简单、纤维形貌可控性强,且制备的纤维比表面积大、孔隙率高、柔性好,经过碳化处理后,不需要粘结剂就可直接作为超级电容器的电极材料。本文综述了近年来常规和新型静电纺柔性电极材料在超级电容器领域应用的最新研究进展,并对其进行了分类,对比了不同种类电极材料的制备方法和后处理工艺。据文献资料报道,基于静电纺纳米纤维膜碳化处理后的电极材料具有大的比表面积和含碳率,通过后处理优化材料的孔结构或者在表面负载金属氧化物,都可以很好地提升其电化学性能,实现其使用效能。除了前驱体原料外,纳米纤维的形貌、预氧化和碳化温度、升温速率,以及通过活化等后处理形成的孔结构等因素都会对电极材料的柔性产生极大影响。本文通过对电极材料的分类、对新材料的介绍,为研究人员开发和使用新材料提供一个方向。此外,本文对提升电极材料电化学性能的诸多方法...     

柔性储能电池电极的设计、制备与应用EI北大核心CSCD

随着便携式、可穿戴电子器件的迅速发展,柔性储能器件的研究逐渐转向微型化、轻柔化和智能化等方向。同时人们对器件的能量密度、功率密度和力学性能有了更高的要求。电极材料作为柔性储能器件的核心部分,是决定器件性能的关键。柔性储能电子器件的发展,又迫切需要新型电池技术和快速、低成本且可精准控制其微结构的制备方法。因此,柔性锂/钠离子电池、柔性锂硫电池、柔性锌空电池等新型储能器件的研发成为目前学术界研究的热点。本文论述了近年来柔性储能电池电极的研究现状,着重对柔性电极材料的设计(独立柔性电极和柔性基底电极)、不同维度柔性电极材料的制备工艺(一维材料、二维材料和三维材料)和柔性储能电极的应用(柔性锂/钠离子电池、柔性锂硫电池、柔性锌空电池)进行对比分析,并对电极材料的结构特性和电化学性能进行了讨论。最后,指出了柔性储能器件目前所面临的问题,并针对此类问题展望了柔性储能器件未来的重点在于新型固态电解质的研发、器件结构的合理设计及封装技术的不断优化。     

碳纤维/棉纤维/聚吡咯柔性复合材料的制备及性能研究

柔性超级电容器作为一种储能器件,具有功率密度高、充电时间短、循环寿命长、比电容高等优点,可满足可穿戴器件的需求,而柔性电极材料是决定柔性超级电容器发展的关键因素,它决定着电容器的主要性能指标。采用混纺的方法制备了碳纤维含量为20%(质量分数)的碳纤维/棉纤维混纺纱线,然后通过电化学沉积法在碳纤维/棉纤维混纺纱线上生长聚吡咯颗粒,成功制备了20%(质量分数)碳纤维/棉纤维/聚吡咯柔性复合材料。利用扫描电子显微镜、拉曼光谱分析仪和电化学工作站研究了复合材料的形貌、聚吡咯沉积情况以及复合材料的电容性能。结果表明,20%(质量分数)碳纤维/棉纤维/聚吡咯柔性复合材料中,聚吡咯颗粒直径为30~60 nm,且沉积均匀,化学活性较高;在1.02 mA/cm^2电流密度下,复合材料的最大比电容达到1.28 F/cm^2,其高比电容归因于电极的独特结构;复合材料具有良好的柔韧性、机械稳定性和充放电循环寿命,其经过6000次弯曲循环后,电容保持率仍有80%以上,可以用作柔性可穿戴超级电容器的电极材料。     

三维结构应用于储能器件的研究进展

锂离子电池和超级电容器作为新型储能器件因具有能量密度高、充放电效率高、绿色环保等诸多优点，能够应用于能源、汽车、电子器件等领域，备受研究者的关注。三维结构能够增大电极材料的单位立足面积，有效提高电极材料的利用效率，显著改善储能器件的电化学性能。为了进一步提升储能器件的电化学性能和拓宽其应用领域，设计制备具有3D结构的电极材料显得非常必要。主要对利用三维结构电极材料制备锂离子电池和超级电容器进行综述，分析了不同三维结构制备储能器件的优点以及存在的问题，并对三维储能器件的发展方向进行了展望。     

柔性超级电容器复合电极材料的研究进展

随着智能电子设备的不断更新换代,研发者们开始研制更加符合人们需求的电子设备,于是一种柔性可穿戴电子设备映入人们眼帘,柔性超级电容器作为一类便携式能量储存设备也受到了许多研究者的关注。其中电极是超级电容器的核心,而电极材料的选择又直接关乎超级电容器的储能本领和其它性能,于是决定力学性能及其电化学性能好坏的柔性电极材料是我们目前主要的研究对象。目前,超级电容器对电极材料的研究不仅限于某一种单一材料,重点集中在材料的复合化上,其中以掺杂改性电极材料的研究为多。首先介绍了超级电容器的性能特点和研究进展,其次重点概述了不同电极材料所具有的力学性能和电化学性能,最后对柔性电容器电极材料的研究进行了展望,希望能为柔性电容器的探究提供参考和借鉴。     

具有高容量和优异倍率性能的柔性超级电容器

正随着便携、可穿戴电子设备的发展,柔性的超级电容器得到越来越广泛的关注和研究,以适应不同应用领域的储能需求。在柔性超级电容器中,具有高容量、高充放电倍率性能的柔性电极材料的设计和制备至关重要。石墨烯和导电聚苯胺分别具有双电层电容和赝电容的储能特性,是两类最具代表性的超级电容器电极材料。通过在纳米     

聚乙烯醇基凝胶电解质的制备及在储能器件中的应用

由于在电化学能源存贮与转化器件中所展现出的巨大潜在应用前景,固态聚合物电解质膜的开发受到研究界的广泛关注。基于柔性储能与转换器件的发展,以聚乙烯醇(Polyvinyl alcohol, PVA)为基体的凝胶聚合物电解质(Gel polymer electrolytes, GPEs)因亲水性强,无毒,良好的兼容性以及优异的化学稳定性,是当前研究较多的理想电解质材料。本文从PVA基水凝胶电解质的制备合成原理、方法和性能表征出发,总结和讨论了其基本物理特性和电化学性能,并就PVA基水凝胶电解质在超级电容器、柔性锌空电池、锂离子电池以及太阳能水热电池中的研究和应用进展进行了综述,并对其在该领域未来的发展做出展望。     

基于超级电容器的多孔电极材料研究进展

目前,对能源的需求急剧增加,超级电容器作为绿色储能器件备受关注。超级电容器按储能机理可分为双电层电容器及法拉第赝电容器两种。双电层电容器的电极材料主要由炭基材料组成,法拉第赝电容器的电极材料主要由导电聚合物及金属氧化物构成;炭基材料与导电聚合物或金属氧化物等复合产生的协同作用可获得更优异的电化学性能。多孔电极材料由于其大的比表面积、独特的多孔结构、多样化的组成和优异的电子导电性而引起了广泛的关注。总结了具有微观多孔结构的超级电容器材料的制备方法以及结构-性能的关系,对比指出多孔超级电容器电极材料因其更高的比表面积和孔隙率而更有利于获得高性能超级电容器。     

柔性染料敏化太阳能电池和柔性钙钛矿太阳能电池关键电极材料研究进展

柔性太阳能电池具有轻便、可弯曲的优点,可用于可穿戴设备等器件的即时充电,具有广阔的应用前景,受到持续广泛的关注。柔性太阳能电池制备中的关键在于基材以及与之相关的电极材料的制备。本文综述了柔性染料敏化太阳能电池和柔性钙钛矿太阳能电池近几年的发展情况,着重介绍了柔性染料敏化太阳能电池光阳极、对电极以及柔性钙钛矿太阳能电池的底电极和电子传输层。结果发现高温烧结目前仍是制备高效染料敏化太阳能电池光阳极不可避免的方法,而对电极则不受这一限制并且已经有多种材料的效率超过了高温烧结的铂。柔性钙钛矿太阳能电池的研究重点是用其他材料代替底电极中柔性较差的ITO以及高温烧结的电子传输材料TiO₂,并且都取得显著成效。在此基础上,展望了柔性染料敏化太阳能电池和柔性钙钛矿太阳能电池未来的发展方向。     

Conducting Polymer Nanowire Arrays for High Performance Supercapacitors

This Review provides a brief summary of the most recent research developments in the fabrication and application of one‐dimensional ordered conducting polymers nanostructure (especially nanowire arrays) and their composites as electrodes for supercapacitors. By controlling the nucleation and growth process of polymerization, aligned conducting polymer nanowire arrays and their composites with nano‐carbon materials can be prepared by employing in situ chemical polymerization or electrochemical polymerization without a template. This kind of nanostructure (such as polypyrrole and polyaniline nanowire arrays) possesses high capacitance, superior rate capability ascribed to large electrochemical surface, and an optimal ion diffusion path in the ordered nanowire structure, which is proved to be an ideal electrode material for high performance supercapacitors. Furthermore, flexible, micro‐scale, threadlike, and multifunctional supercapacitors are introduced based on conducting polyaniline nanowire arrays and their composites. These prototypes of supercapacitors utilize the high flexibility, good processability, and large capacitance of conducting polymers, which efficiently extend the usage of supercapacitors in various situations, and even for a complicated integration system of different electronic devices.     

An All‐Freeze‐Casting Strategy to Design Typographical Supercapacitors with Integrated Architectures

The emergence of flexible and wearable electronics has raised the demand for flexible supercapacitors with accurate sizes and aesthetic shapes. Here, a strategy is developed to prepare flexible all‐in‐one integrated supercapacitors by combining all‐freeze‐casting with typography technique. The continuous seamless connection of all‐in‐one supercapacitor devices enhances the load and/or electron transfer capacity and avoids displacing and detaching between their neighboring components at bending status. Therefore, such a unique structure of all‐in‐one integrated devices is beneficial for retaining stable electrochemical performance at different bending levels. More importantly, the sizes and aesthetic shapes of integrated supercapacitors could be controlled by the designed molds, like type matrices of typography. The molds could be assembled together and typeset randomly, achieving the controllable construction and series and/or parallel connection of several supercapacitor devices. The preparation of flexible integrated supercapacitors will pave the way for assembling programmable all‐in‐one energy storage devices into highly flexible electronics.     

Recent Advances in Fiber Supercapacitors: Materials,Device Configurations,and Applications

Fiber supercapacitors (SCs), with their small size and weight, excellent flexibility and deformability, and high capacitance and power density, are recognized as one of the most robust power supplies available for wearable electronics. They can be woven into breathable textiles or integrated into different functional materials to fit curved surfaces for use in day-to-day life. A comprehensive review on recent important development and progress in fiber SCs is provided, with respect to the active electrode materials, device configurations, functions, integrations. Active electrode materials based on different electrochemical mechanisms and intended to improve performance including carbon-based materials, metal oxides, and hybrid composites, are first summarized. The three main types of fiber SCs, namely parallel, twist, and coaxial structures, are then discussed, followed by the exploration of some functions including stretchability and self-healing. Miniaturized integration of fiber SCs to obtain flexible energy fibers and integrated sensing systems is also discussed. Finally, a short conclusion is made, combining with comments on the current challenges and potential solutions in this field.     

Flexible Energy‐Storage Devices: Design Consideration and Recent Progress

Flexible energy‐storage devices are attracting increasing attention as they show unique promising advantages, such as flexibility, shape diversity, light weight, and so on; these properties enable applications in portable, flexible, and even wearable electronic devices, including soft electronic products, roll‐up displays, and wearable devices. Consequently, considerable effort has been made in recent years to fulfill the requirements of future flexible energy‐storage devices, and much progress has been witnessed. This review describes the most recent advances in flexible energy‐storage devices, including flexible lithium‐ion batteries and flexible supercapacitors. The latest successful examples in flexible lithium‐ion batteries and their technological innovations and challenges are reviewed first. This is followed by a detailed overview of the recent progress in flexible supercapacitors based on carbon materials and a number of composites and flexible micro‐supercapacitors. Some of the latest achievements regarding interesting integrated energy‐storage systems are also reviewed. Further research direction is also proposed to surpass existing technological bottle‐necks and realize idealized flexible energy‐storage devices.     

Fabrication of Metal Molybdate Micro/Nanomaterials for Electrochemical Energy Storage

Currently, metal molybdates compounds can be prepared by several methods and are considered as prospective electrode materials in many fields because the metal ions possess the ability to exist in several oxidation states. These multiple oxidation states contribute to prolonging the discharge time, improving the energy density, and increasing the cycling stability. The high electrochemical performance of metal molybdates as electrochemical energy storage devices are discussed in this review. According to recent publications and research progress on relevant materials, the investigation of metal molybdate compounds are discussed via three main aspects: synthetic methods, material properties and measured electrochemical performance of these compounds as electrode materials. The recent progress in general metal molybdate nanomaterials for LIBs and supercapacitors are carefully presented here.     

Flexible and Stretchable Energy Storage: Recent Advances and Future Perspectives

Energy‐storage technologies such as lithium‐ion batteries and supercapacitors have become fundamental building blocks in modern society. Recently, the emerging direction toward the ever‐growing market of flexible and wearable electronics has nourished progress in building multifunctional energy‐storage systems that can be bent, folded, crumpled, and stretched while maintaining their electrochemical functions under deformation. Here, recent progress and well‐developed strategies in research designed to accomplish flexible and stretchable lithium‐ion batteries and supercapacitors are reviewed. The challenges of developing novel materials and configurations with tailored features, and in designing simple and large‐scaled manufacturing methods that can be widely utilized are considered. Furthermore, the perspectives and opportunities for this emerging field of materials science and engineering are also discussed.     

Binder-free activated carbon/carbon nanotube paper electrodes for use in supercapacitors

Novel inexpensive, light, flexible, and even rollup or wearable devices are required for multi-functional portable electronics and developing new versatile and flexible electrode materials as alternatives to the materials used in contemporary batteries and supercapacitors is a key challenge. Here, binder-free activated carbon (AC)/carbon nanotube (CNT) paper electrodes for use in advanced supercapacitors have been fabricated based on low-cost, industrial-grade aligned CNTs. By a two-step shearing strategy, aligned CNTs were dispersed into individual long CNTs, and then 90 wt%–99 wt% of AC powder was incorporated into the CNT pulp and the AC/CNT paper electrode was fabricated by deposition on a filter. The specific capacity, rate performance, and power density of the AC/CNT paper electrode were better than the corresponding values for an AC/acetylene black electrode. The capacity reached a maximum value of 267.6 F/g with a CNT loading of 5 wt%, and the energy density and power density were 22.5 W·h/kg and 7.3 kW/kg at a high current density of 20 A/g. The AC/CNT paper electrode also showed a good cycle performance, with 97.5% of the original capacity retained after 5000 cycles at a scan rate of 200 mV/s. This method affords not only a promising paper-like nanocomposite for use in low-cost and flexible supercapacitors, but also a general way of fabricating multi-functional paper-like CNT-based nanocomposites for use in devices such as flexible lithium ion batteries and solar cells.