Fundamental Study of Interaction of Ions Present in Water with Graphene Coatings for Energy Harvesting

该项目将研究一种基于水等流体与石墨烯表面相互作用的能量收集方法。石墨烯是一种高度灵活的二维碳原子片，非常适合于大型表面的涂层。该项目旨在证明流经石墨烯表面的水可以直接发电。石墨烯非常适合这一应用，因为它拥有高迁移率的电荷载流子，随时可以与流动流体中存在的移动离子耦合。石墨烯还很灵活，侵入性最小(它是最薄的材料)，化学和机械性能稳定，对环境无害。此外，它的合成是可扩展的，并且可以通过卷到卷沉积技术来制备宏观尺度的连续石墨烯薄膜。拟议中的石墨烯涂层为从雨水、潮汐作用、波浪、洋流、河水以及船只、潜艇和桥梁上的水流等迄今尚未开发的可再生能源收集能源提供了独特的可能性。这种石墨烯外壳可以将水直接转化为电能，从而获得无处不在的、丰富的和可再生的机械能。与传统方案不同，石墨烯涂层直接将流动能量转化为电能，而不需要移动部件。这种石墨烯涂层还可以在低功率、低电压和长寿命的应用中取代传统电池(对环境有害)。与当前技术的渐进式进步相比，一旦扩大规模，这一概念提供了一种潜在的变革性能源收集方法。研究人员将开发专门设计的互动学习模块(或虚拟实验室)，并将其整合到课程中。外展活动包括向本科生以及高中生和教师进行示威。PIs的目的是普及科学，并吸引代表不足的群体从事可再生能源技术的职业。该项目将解决与开发用于纳米流体动力收集的石墨烯涂层相关的基础科学和工程挑战。关键的科学挑战涉及深入理解负责在石墨烯薄膜中收集纳米流体能量的机制(S)。特别是，该项目旨在对水等流体中存在的离子如何与石墨烯涂层以及独立的石墨烯表面相互作用和耦合有一个基本的了解。这将通过精心设计的控制实验，结合分子动力学和第一性原理密度泛函理论计算来解决。工程上的挑战同样重要，它涉及以保持涂层出色的功率密度的方式扩大石墨烯的尺寸。这将通过采用新开发的卷对卷和模板导向的化学气相沉积技术来解决，以生产大规模的石墨烯薄膜和泡沫。石墨烯的制造过程将得到优化，以避免薄膜中的物理界面(破裂)，因为它被放大到宏观尺寸，并严格控制石墨烯的厚度和结构性能。实验和理论、建模和模拟工作之间的耦合将建立对基础科学的基本理解，并使拟议技术的成功开发、优化和验证成为可能。PIS将开发专门设计的互动学习模块(或虚拟实验室)，并将其纳入课程。外展活动包括向本科生以及高中生和教师进行示威。PIS的目的是普及科学，吸引代表不足的群体在可再生能源技术方面追求职业生涯。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project will investigate an approach to energy harvesting based on the interaction of a fluid such as water with a graphene surface. Graphene is a highly flexible, two-dimensional sheet of carbon atoms and is ideally suited for the coating of large surfaces. This project aims to demonstrate that water flow over graphene surfaces can directly generate electricity. Graphene is ideally suited for this application, since it possesses high-mobility charge carriers that are ready to be coupled to moving ions present in the flowing fluid. Graphene is also flexible, minimally invasive (it is the thinnest material), chemically and mechanically stable, and environmentally benign. Moreover, its synthesis is scalable and macro-scale continuous graphene films can be produced by roll-to-roll deposition techniques. The proposed graphene coating offers unique possibilities for energy harvesting from hitherto untapped renewable sources such as rain, tidal action, waves, ocean currents, river water as well as water flow over boats, submarines, and bridges. Such graphene skins could enable harvesting of the ubiquitous, abundant and renewable mechanical energy of moving water directly to electrical energy. Unlike traditional schemes, the graphene coating directly converts the flow energy into electrical energy without the need for moving parts. Such graphene coatings could also replace conventional batteries (which are environmentally hazardous) in low-power, low-voltage and long service-life applications. Once scaled up, this concept offers a potentially transformative approach to energy harvesting, as compared with incremental advances in current technologies. The investigators will develop specially designed interactive learning modules (or virtual labs) which will be integrated into the curriculum. Outreach includes demonstrations to undergraduates as well as to high school students and teachers. The PIs aim is to popularize science and to attract under-represented groups to pursue careers in renewable energy technologies. This project will tackle the fundamental science and engineering challenges associated with developing graphene-based coatings for nano-fluidic power harvesting. The key science challenge involves understanding in-depth the mechanism(s) responsible for nano-fluidic power harvesting in graphene films. In particular, the project aims to develop a fundamental understanding of how ions present in a fluid such as water, interact and couple with graphene-coated as well as free-standing graphene surfaces. This will be addressed using carefully designed control experiments in conjunction with molecular dynamics and first principles density functional theory calculations. The engineering challenge is equally important and involves scaling up the graphene size in a manner that retains the outstanding power density of the coating. This will be addressed by adapting newly developed roll-to-roll and template-directed chemical vapor deposition techniques to produce macroscale graphene films and foams. The graphene manufacturing process will be optimized to avoid physical interfaces (breaks) in the film as it is scaled up to macroscale dimensions and to tightly control thickness and structure-properties of the graphene. The coupling between experiments and theory, modeling and simulation work will build fundamental understanding of the underlying science and enable successful development, optimization and validation of the proposed technology. The PIs will develop specially designed interactive learning modules (or virtual labs) which will be integrated into the curriculum. Outreach includes demonstrations to undergraduates as well as to high school students and teachers. The PIs aim is to popularize science and to attract under-represented groups to pursue careers in renewable energy technologies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.