EPSRC-SFI: Next Generation Energy Autonomous Textile Fabrics based on Triboelectric Nanogenerators (NextGenT-TENG)

近年来，可穿戴电子设备和传感器（例如健身监测器、智能手表、心电图（ECG）传感器等）的使用大幅增加。在过去的十年中，可穿戴系统的能力取得了重大进展;然而，性能的提高不可避免地导致电子设备的小型化，这意味着未来需要更多的传感器和更高的功率要求。目前，迫切需要提供充足且自主的清洁电源，以避免依赖笨重且不环保的电池组。纺织摩擦电纳米发电机（T-TENG）提供了一个解决方案。摩擦电纳米发电机（TENG）使用两个适当选择的表面的循环接触将机械能转换为电能。T-TENG是简单的TENG，其中摩擦接触材料被纳入可穿戴纺织品中，能够将人类运动中的能量转换为电能，例如日常行走和手臂运动。目前;然而，T-TENG的性能明显落后于传统的散装TENG，不足以为大多数电子纺织系统提供动力。该项目将开发下一代高性能纺织摩擦电纳米发电机，能够满足当前和未来可穿戴系统的能源需求。它还将开发技术，将T-TENG纳入完全集成的能源自主结构中。我们将通过以下方法实现T-TENG性能的这种阶跃变化。首先，这个问题是多学科的，这在以前阻碍了全面的发展。因此，该项目将电子工程，摩擦学，材料化学和纺织技术领域联系起来，以创建了解设备性能所有关键方面所需的能力。接下来，认识到设备设计需要严格的科学基础，我们将对纺织品摩擦接触的基础物理学有一个基本的了解。这将最终导致考虑T-TENG的力学和静电学的器械性能预测模型。我们知道，输出与界面处可以产生的摩擦变化密度有很大关系。在这里，我们认为，最大限度地提高亲和力（即摩擦材料之间）和接触面积的差异将是至关重要的。因此，我们将优化纺织品的材料、纤维结构和表面形貌，以最大限度地提高这两个关键参数。在界面材料上，我们将使用电子亲和力差异最大的材料对。这将采取金属氧化物涂层纤维与传统纺织纤维如聚酯和聚丙烯接触的形式。在纤维架构方面，我们将使用我们的预测T-TENG模型来设计最大化接触面积的纤维架构。在表面形貌方面，我们将率先使用分支纳米丝或纳米柱，以进一步提高接触面积。为了在纺织品上实现这些涂层和表面特征，该项目将开发一些新的加工技术。然后，所有这些方面将统一在一个单一的设备设计中，并将进一步修改和完善。然后，优化的T-TENG将与基于纺织品的传感器系统完全集成，形成完全能量自主的织物。最后，将建造一个技术演示器，向学术界和工业界展示输出性能。我们将与我们的工业合作伙伴Kyrima和Pireta密切合作，他们都在为电子纺织品行业开发新技术方面经验丰富。一个成功的结果将意味着医疗和娱乐领域的许多可穿戴系统可以使用清洁和免费的能源来供电：简单的日常人类运动。

In recent years there has been a major surge in the use of wearable electronic devices & sensors (such as fitness monitors, smart watches, electrocardiogram (ECG) sensors etc.). The last decade has led to major advances in the capability of wearable systems; however, performance enhancement inevitably leads to miniaturisation of electronics meaning more sensors and increased power requirements going forward. At present, there is an urgent need to provide a sufficient and autonomous source of clean power to avoid dependence on cumbersome & environmentally unfriendly battery packs. The textile triboelectric nano generator (T-TENG) offers a solution. Triboelectric nano generators (TENGs) use the cyclic contact of two suitably chosen surfaces to convert mechanical energy to electrical energy. T-TENGs are simply TENGs where the tribo-contact materials are incorporated into wearable textiles capable of converting energy in human motions such as daily walking & arm movements into electricity. At present; however, T-TENG performance lags significantly behind that of conventional bulk TENGs and is insufficient to power most e-textile systems.This project will develop a next generation of high performance textile triboelectric nano generator capable of meeting the current and future energy requirements of wearable systems. It will also develop technology to incorporate the T-TENG in fully integrated energy autonomous fabrics. We will achieve this step-change in T-TENG performance via the following approach. First, the problem is intensely multidisciplinary and this has previously hampered development of a full picture. Therefore, this project unties the fields of electronic engineering, tribology, materials chemistry, and textiles technology to create the capability required to understand all key aspects of device performance. Next, recognising the need for a rigorous scientific foundation for device design, we will develop a fundamental understanding of the underlying physics of the tribo-contact of textiles. This will culminate in a predictive model for device performance accounting for both the mechanics and electrostatics of the T-TENG. We know that output is hugely linked to the amount of tribo-change density that can be developed at the interface. Here, we contend that maximising difference in election affinity (i.e. between the tribo-materials) and contact area will be critical. Therefore, we will optimise the materials, fibre architecture and surface topography of the textiles to maximise these two key parameters. On interface materials, we will implement the use of material pairs with maximum difference in electron affinity. This will take the form of metal oxide coated fibres in contact with conventional textile fibres such as polyester and polypropylene. On fibre architecture, we will use our predictive T-TENG model to design a fibre architecture that maximises contact area. On surface topography, we will pioneer the use of branching nano filaments or nano pillars to further enhance contact area. To implement these coatings and surface features on textile fabrics, the project will develop a number of novel processing techniques. All of these aspects will then be united in a single device design which will be further modified and refined. The optimised T-TENG will then be fully integrated with a textile based sensor system to form a fully energy autonomous fabric. Finally, a technology demonstrator will be built to demonstrate output performance to both academia & industry. We will work closely with our industrial partners Kyrima & Pireta who are both highly experienced in developing new technologies for the e-textiles industry. A successful outcome would mean that a host of wearable systems in the medical and entertainment sectors could be powered using a clean and free source of energy: that of simple everyday human motion.