Quantum nanodots and core shell structures in polymer insulation and materials for energy storage

人们普遍接受化石燃料对地球大气层的影响，这导致发展中国家和发达国家对可再生能源发电技术进行了大量投资。例如，2015年，印度大幅增加了对可再生能源的承诺，设定了到2022年达到175吉瓦的目标，而欧盟的2030年气候和能源框架旨在将温室气体排放量相对于1990年水平减少40%，并利用27%的可再生能源。然而，可再生能源发电通常远离需求中心，因此，这种变化对电力传输系统产生重大影响。这一问题在德国得到了很好的证明，在德国，公众对架空电力线的接受程度较低，这意味着Suedlink项目将需要安装一条700公里、500千伏的地下高压直流输电线路，从北方沿海地区连接到该国中部和南部的需求中心，以便整合海上风力发电。事实上，总的来说，TransnetBW GmbH估计德国将需要新的HVDC输电走廊，总长度在2600和3100 km之间，总输电容量为12 GW。新一代电缆技术的发展促进了上述雄心勃勃的计划，其中绝缘系统的进步尤其是聚乙烯的改进至关重要。例如，2014年，ABB报告了一种新的525 kV高压直流挤压电缆系统，随后NKT在2017年对其进行了改进，将工作电压提高到640 kV。这些进步从根本上建立在材料改进的基础上，特别是降低交联聚乙烯（XLPE）绝缘内污染水平的新策略，这可能是由于绝缘系统内过氧化二异丙苯（DCP）交联残留物的保留和周围绝缘层中不稳定物质的扩散。这两个来源已被证明会影响绝缘内的电荷传输动力学和不利影响performance.Project目标：在这个项目中，我们将进行第一个实验调查有关最近的主张，其中添加纳米粒子可以修改绝缘聚合物的电气行为。自从刘易斯在1994年首次提出这种策略的潜在好处以来，对该机制的理解集中在位于聚合物基体内的界面区域的发展上。这种方法有一些早期的承诺，但经过二十年的尝试解锁所谓的“界面区域”，即在纳米颗粒和主体聚合物之间的界面处在聚合物内产生的建议体积，实际证据仍然很少。因此，最近，T. Tanaka提出了一种新的“量子点”模型，其中关键区域位于纳米颗粒本身内。这方面的开创性工作是在南安普顿大学进行的，导致2018年出版了“引入粒子界面模型来描述纳米电介质的电学行为”。这项工作加上田中的原始文件导致早稻田大学，日本，博洛尼亚大学，意大利和南安普顿大学的国际合作的开始。该项目将考虑聚合物/量子点系统，并将探索相关结构参数对全局电特性的影响。通过独立控制核壳结构中的核和壳，以及它们对整体电学性质的影响，我们期望回答纳米颗粒如何影响电荷行为的问题。这将反过来允许更可靠的能量密度和更高的能量密度。

The generally acceptance of the impact of fossil fuels fuel on the planet's atmosphere has led to significant investments in renewable generation technologies in both developing and developed economies. For example, in 2015, India dramatically increased its commitment to renewables by setting a target of 175 GW by 2022, while the European Union's 2030 climate and energy framework aims to reduce greenhouse gas emission by 40%, relative to 1990 levels, and exploit 27% of renewable energy. However, renewable sources of electrical generation are generally located far from centres of demand and such changes therefore have major implications for electricity transmission systems. This problem is well demonstrated in Germany, where low public acceptance of overhead power lines means that the Suedlink project will require the installation of a 700 km, 500 kV underground high-voltage direct current (HVDC) link from the northern seaboard to demand centres in the centre and south of the country, in order to integrate offshore wind generation. Indeed, in total, TransnetBW GmbH has estimated that Germany will require new HVDC transmission corridors with a total length of between 2600 and 3100 km and with a total transmission capacity 12 GW.Ambitious plans such as those outlined above are being facilitated by the development of new generations of cable technologies where advances in insulation systems in general and refinements in polyethylene in particular are critical. For example, in 2014, ABB reported on a new 525 kV HVDC extruded cable system, which was subsequently refined by NKT in 2017 to increase the operating voltage to 640 kV. These advances are fundamentally built upon materials refinements and, in particular, novel strategies to reduce contamination levels within the crosslinked polyethylene (XLPE) insulation, which may arise from both the retention of dicumyl peroxide (DCP) crosslinking residues within the insulation system and the diffusion of labile species from the surrounding semiconductive layers. Both of these sources have been shown to affect charge transport dynamics within the insulation and adversely affect performance.Project goals:In this project we will conduct the first experimental investigations relating to recent propositions by which the addition of nanoparticles can modify the electrical behavior of insulating polymers. Since the potential benefits of this strategy were first proposed by Lewis in 1994, understanding of the mechanism have focused on the development of interphase regions located within the polymer matrix. This approach had some early promise, but after two decades of trying to unlock the so-called "interphase region", the suggested volume that is created within the polymer at the interface between nanoparticles and the host polymer, actual evidence is still scarce. As a consequence, more recently, T. Tanaka has suggested a new "Quantum Dot" model, whereby the key regions are located within the nanoparticles themselves. Pioneering work in this regard was performed at the University of Southampton, leading to publication of "Introducing particle interphase model for describing the electrical behaviour of nanodielectrics" in 2018. This work together with Tanaka's original paper lead to the start of an international collaboration of Waseda University, Japan, University of Bologna, Italy and the University of Southampton. This project will consider polymer/quantum dot systems and will explore the influence of pertinent structural parameters on the global electrical characteristics. By controlling the core and shell of core-shell structures independently, and their effect on global electrical properties, we expect to answer the question how nanoparticles affect charge behavior. This will, in turn, allow more reliable dielectrics and higher energy densities.