储能介电玻璃陶瓷的制备及研究进展

介电玻璃陶瓷因具有玻璃的高耐电击穿性,以及介电材料的高介电常数,成为脉冲功率技术中最有潜力的储能材料候选之一。本文简要阐述了介电玻璃陶瓷的能量存储原理,重点介绍了其制备方法、当前研究关注的类别体系以及影响该类玻璃陶瓷材料储能密度的因素。     

超级电容器储能材料的研究进展

超级电容器高的电能储存密度以及长的使用寿命引起了世界范围内的关注.通过参考和整理当前超级电容器的研究进展,介绍了两大类超级电容器的原理、主要性能、目前的发展情况和特点.同时,总结了改善和提高超级电容器储能密度的各种材料的选取、制备工艺和途径.在此基础上,认为电化学超级电容器比电介质超级电容器具有更大的储能密度及市场前景.然而,由于电介质超级电容器的独特性能,其在一些电子电气设备、元器件的应用中具有不可替代的作用,值得深入研究.     

高储能密度玻璃陶瓷材料的研究进展

介绍了电介质材料储能密度的概念,综述了陶瓷及玻璃陶瓷用于储能介质材料的研究进展,重点分析了影响介质材料储能密度的若干因素,展望了玻璃陶瓷电容器在军事、混合动力汽车及生物医学上的应用前景,指出了今后高储能密度介质材料的发展方向。     

聚酰亚胺纳米泡沫介电材料研究进展

介绍一种孔洞尺寸为纳米级、介电常数低于２．４的芳香性聚酰亚胺泡沫新材料及其制备方法、影响结构与性能的因素、应用前景及存在的问题。     

尖晶石结构磁介电材料的研究进展

随着通信技术的发展,对无限通信设备的集成度有了更高的要求,天线小型化成为目前重要的研究方向。等磁介电材料是一种既具有磁导率又具有介电常数,且磁导率和介电常数几乎相等的材料,使用等磁介电材料作为天线的基板,能有效的减小天线的尺寸,提高带宽,增加辐射效率。铁氧体是由Fe2O3和一种或多种金属氧化物复合而成,具有较高的磁导率和介电常数,由于其同时具有磁特性和介电特性,是一种潜在的等磁介电材料。综述了近几年尖晶石结构磁介电材料的国内外研究进展,着重讨论了掺杂改性对烧结温度、磁导率、介电常数、直流电阻等电磁特性的影响。最后指出目前研究中存在的问题,并展望了该材料在未来发展的方向。     

铁电材料介电非线性研究进展

铁电材料是一类重要的功能材料,介电(电压)非线性是近年来高新技术研究的前沿和热点之一.综述了关于铁电材料介电非线性的临界尺寸、晶粒尺寸效应、膜厚效应、模型和介质移相器等方面的最新研究进展,提出了研究中需要解决的一些问题.     

高储能密度聚合物基多层复合电介质的研究进展

薄膜电容器是现代电力装置与电子设备的核心电子元件,受限于薄膜介质材料的介电常数偏低,当前薄膜电容器难以获得高储能密度(指有效储能密度,即可释放电能密度),从而导致薄膜电容器体积偏大,应用成本过高。将具有高击穿场强的聚合物与高介电常数的纳米陶瓷颗粒复合,制备聚合物/陶瓷复合电介质,是实现薄膜电容器高储能密度的有效策略。对于单层结构的0-3型聚合物/陶瓷复合电介质,其介电常数与击穿场强难以同时获得有效提升,限制了储能密度的进一步提高。为了解决此矛盾,研究者们叠加组合高介电常数的复合膜与高击穿场强的复合膜,制备了2-2型多层复合电介质,能够协同调控极化强度与击穿场强来获取高储能密度。研究表明,调控多层复合电介质的介观结构与微观结构,可以实现优化电场分布、协同调控介电常数与击穿场强等目标。本文综述了近年来包括陶瓷/聚合物和全有机聚合物在内的多层聚合物基复合电介质的研究进展,重点阐述了多层结构调控策略对储能性能的提升作用,总结了聚合物基多层复合电介质的储能性能增强机制,并讨论了当前多层复合电介质面临的挑战和发展方向。     

一种新型高储能密度定形相变材料

采用山梨醇和对甲基苯甲醛合成了1,3∶2,4-二(4-甲基苯甲醛)山梨醇(MDBS),并将其作为石蜡类定形复合相变材料(PCM)的凝胶因子,然后以利用凝胶因子形成的三维网络结构作为石蜡的支撑材料,制备了一系列高储能密度的定形复合相变材料。对其进行凝胶解缔温度测试和泄漏量测试发现,添加一定量MDBS制备定形复合相变材料,可使定形复合相变材料中主储能材料——石蜡的含量大幅提高到90%以上,同时也为复合定形相变材料的开发提供了一条新的研究思路。     

基于第一性原理反演的介电材料设计方法研究

在分析目前基于第一性原理的介电材料性能预测和研究方法的基础上,提出基于第一性原理的介电材料反演设计思想和方法,即以材料的介电性能需求为出发点,依据第一性原理的性能预测正向模型,反演材料所需满足的结构特点以及原子(分子)组成,指出了必须研究解决的电磁(光)场的量子化结构、电介质量子化极化理论、全波段介电性质归一化计算和材料反演模型等关键科学问题和研究重点。该方法的研究有望为目前以经验式、半经验式以及计算机模拟辅助为主的材料设计提供一种新的研究思路。     

Flexible Nanodielectric Materials with High Permittivity for Power Energy Storage

Study of flexible nanodielectric materials (FNDMs) with high permittivity is one of the most active academic research areas in advanced functional materials. FNDMs with excellent dielectric properties are demonstrated to show great promise as energy‐storage dielectric layers in high‐performance capacitors. These materials, in common, consist of nanoscale particles dispersed into a flexible polymer matrix so that both the physical/chemical characteristics of the nanoparticles and the interaction between the nanoparticles and the polymers have crucial effects on the microstructures and final properties. This review first outlines the crucial issues in the nanodielectric field and then focuses on recent remarkable research developments in the fabrication of FNDMs with special constitutents, molecular structures, and microstructures. Possible reasons for several persistent issues are analyzed and the general strategies to realize FNDMs with excellent integral properties are summarized. The review further highlights some exciting examples of these FNDMs for power‐energy‐storage applications.     

Storage of Mechanical Energy Based on Carbon Nanotubes with High Energy Density and Power Density

Energy storage in a proper form is an important way to meet the fast increase in the demand for energy. Among the strategies for storing energy, storage of mechanical energy via suitable media is widely utilized by human beings. With a tensile strength over 100 GPa, and a Young's modulus over 1 TPa, carbon nanotubes (CNTs) are considered as one of the strongest materials ever found and exhibit overwhelming advantages for storing mechanical energy. For example, the tensile‐strain energy density of CNTs is as high as 1125 Wh kg^‐1. In addition, CNTs also exhibit great potential for fabricating flywheels to store kinetic energy with both high energy density (8571 Wh kg^‐1) and high power density (2 MW kg^‐1 to 2 GW kg^‐1). Here, an overview of some typical mechanical‐energy‐storage systems and materials is given. Then, theoretical and experimental studies on the mechanical properties of CNTs and CNT assemblies are introduced. Afterward, the strategies for utilizing CNTs to store mechanical energy are discussed. In addition, macroscale production of CNTs is summarized. Finally, future trends and prospects in the development of CNTs used as mechanical‐energy‐storage materials are presented.     

BaTiO3纳米线的制备及其复合物介电和储能性能研究

采用两步水热法合成钛酸钡(BaTiO₃)纳米线, 并以此为填充物, 聚偏氟乙烯六氟丙烯(P(VDF-HFP))为聚合物基体制备介电复合物, 研究不同含量BaTiO₃纳米线对复合物的介电及储能性能的影响。采用X射线衍射仪、扫描电镜、透射电镜、阻抗分析仪和铁电工作站等表征BaTiO₃纳米线及其复合物的物相、微观结构、介电和储能性能。结果表明: BaTiO₃纳米线具有典型的四方相, 且在聚合物基体中具有良好的分散性与相容性。相同频率下, 复合物的介电常数随着BaTiO₃纳米线含量的增加而增加。含量为20vol%的复合物, 在1 kHz频率下其介电常数取得最 大值30.69。含量为5vol%的复合物, 在场强为240 kV/mm时, 获得了最大的储能密度与放电能量密度, 分别为4.89和2.58 J/cm³。     

复合相变储能材料制备工艺对其浸渗率和相对密度的影响

本文探索了Na2SO4/SiO2无机盐/陶瓷基复合相变储能材料的自发熔融浸渗工艺制度.讨论了预制体制备工艺的四个主要影响因素:造孔剂含量、成型压力、烧成温度和颗粒粒度与复合相变储能材料的浸渗率和相对密度的关系,分析了熔融盐与预制体浸渗合成时,浸渗温度、浸渗时间以及浸渗方式对复合相变储能材料浸渗率和相对密度的影响.对复合相变储能材料的物相组成和显微结构进行分析,结果表明:制备工艺对复合储能材料的物相组成影响不大,Na2SO4与SiO2两相表现出较好的高温稳定性和相容性,且分布均匀.     

基于矿物特性的太阳能储热材料研究进展

相变材料因其优越潜热被广泛应用于太阳能光热技术中,绝大多数有机相变材料的导热系数非常低,大多介于0.1～0.4 W·m-1·K-1之间。此外,相变材料流动性大,因此需采用导热性能好、具有稳定结构的基体支撑有机相变材料,改善其应用性能。一些天然矿物具有适当的比热与导热系数、多孔道的微结构以及天然的热稳定性与化学兼容性等矿物特性,被用于支撑相变材料制备太阳能储热材料。探讨了矿物的结构特性与性能优势,总结了石墨、珍珠岩、蛭石、硅藻土、埃洛石以及石膏等矿物基太阳能储热材料的制备研究。在此基础上介绍了矿物基太阳能储热材料在太阳能建筑节能、太阳能热水器、太阳能热发电等太阳能光热领域中的应用,并展望了矿物基太阳能储热材料的发展趋势和应用前景。     

Series of Halogen Engineered Ni(OH)2 Nanosheet for Pseudocapacitive Energy Storage with High Energy Density

Ni(OH)₂ nanosheet, acting as a potential active material for supercapacitors, commonly suffers from sluggish reaction kinetics and low intrinsic conductivity, which results in suboptimal energy density and long cycle life. Herein, a convenient electrochemical halogen functionalization strategy is applied for the preparation of mono/bihalogen engineered Ni(OH)₂ electrode materials. The theoretical calculations and experimental results found that thanks to the extraordinarily high electronegativity, optimal reversibility, electronic conductivity, and reaction kinetics could be achieved through F functionalization  . However, benefiting from the largest ionic radius, I Ni(OH)₂ contributes the best specific capacity and morphology transformation, which is a new finding that distinguishes it from previous reports in the literature. The exploration of the interaction effect of halogens (F, I Ni(OH)₂, F, Br Ni(OH)₂, and Cl, I Ni(OH)₂) manifests that F, I Ni(OH)₂ delivers a higher specific capacity of 200.6 mAh g⁻¹ and an excellent rate capability of 58.2% due to the weaker electrostatic repulsion, abundant defect structure, and large layer spacing. Moreover, the F, I Ni(OH)₂//FeOOH@NrGO device achieves a high energy density of 97.4 Wh kg⁻¹ and an extremely high power density of 32426.7 W kg⁻¹, as well as good cycling stability. This work develops a pioneering tactic for designing energy storage materials to meet various demands.     

Strawberry‐like Core–Shell Ag@Polydopamine@BaTiO3 Hybrid Nanoparticles for High‐k Polymer Nanocomposites with High Energy Density and Low Dielectric Loss

Flexible nanocomposites comprising of polymer and high‐dielectric‐constant (high‐k) ceramic nanoparticles are becoming increasingly attractive for dielectric and energy storage applications in modern electronic and electric industry. However, a huge challenge still remains. Namely, the increase of dielectric constant usually at the cost of significant decrease of breakdown strength of the nanocomposites because of the electric field distortion and concentration induced by the high‐k filler. To address this long‐standing problem, by using nano‐Ag decorated core–shell polydopamine (PDA) coated BaTiO₃ (BT) hybrid nanoparticles, a new strategy is developed to prepare high‐k polymer nanocomposites with high breakdown strength. The strawberry‐like BT‐PDA‐Ag based ferroelectric polymer [i.e., poly(vinylideneflyoride‐co‐hexafluroro propylene), P(VDF‐HFP)] nanocomposites exhibit greatly enhanced energy density and significantly suppressed dielectric loss as well as leakage current density in comparison with the nanocomposites with the core–shell structured BT‐PDA. Coulomb‐blockade effect of super‐small nano‐Ag is used to explain the observed performance enhancement of the nanocomposites. The simplicity and scalability of the described approach provide a promising route to polymer nanocomposites for dielectric and energy storage applications.