EAGER: Experimental studies of electrical double-layer capacitance of graphene using van der Waals heterostructures

非技术性：基于石墨烯的电化学器件已显示出传感和储能应用的前景。基于石墨烯的电化学晶体管也被证明可以记录大脑中的电信号。对这类器件感兴趣的一个主要原因是它们易于制造和操作简单。使用电化学设备的新应用需要将这些设备密集集成到大规模功能系统中。然而，这仍然是一项艰巨的挑战。当减小器件尺寸时，难以保持高性能和低可变性。纳米纤维的进步使电化学设备的电化学化成为可能，但仍需要做大量的工作来充分理解控制其操作的基本物理学。这一知识对于实现电化学装置的系统缩小是必不可少的。本项目将通过研究强关联量子系统中的电容来实现这一目标。技术：单位面积的双电层电容是设计小型电化学器件性能的关键指标。研究石墨烯双电层电容的一个重要新的研究方向是借助石墨烯的电子能带结构来考察单位面积的电容。受这一新研究方向的启发，拟议的研究探索了一种新的范式，用于小型化石墨烯电化学器件的双电层电容的精确工程。该范例涉及增强石墨烯中的电子与电解质中的离子之间的相关性。这项研究的研究方法是跨学科的，因为它将使用量子物理学中先进的货车德瓦尔斯石墨烯异质结构来探索电化学中的一个长期存在的问题。具体而言，将使用货车德瓦尔斯石墨烯异质结构作为测试装置结构，其中在异质结构的构造期间将调整石墨烯上的电势分布。为了研究石墨烯中的电势分布对双电层电容的影响，将使用电容-电压和伏安法测量对器件进行电表征。拟议的研究项目可以实现纳米级精度的石墨烯电容的精确工程，同时揭示了将其可实现的值提高到当前极限之外的途径。该项目还将在重要的科学领域培养学生，并为他们提供器件物理学，纳米纤维和分析方法方面的专业知识。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

Nontechnical:Electrochemical devices based on graphene have shown promise for sensing and energy storage applications. Graphene-based electrochemical transistors have also been demonstrated to record electrical signals in the brain. A major reason for interest in this family of devices is their ease of fabrication and simple operation. New applications using electrochemical devices require dense integration of these devices into large-scale functional systems. This has, however, remained a difficult challenge. It is difficult to maintain high performance and low variability when reducing device dimensions. Advances in nanofabrication make it possible to miniaturize electrochemical devices, but much work still needs to be done to fully understand the underlying physics that governs their operation. This knowledge is essential to enable systematic downscaling of the electrochemical devices. This project will make important progress towards that goal by studying capacitance in a strongly correlated quantum system.Technical:Electrical double-layer capacitance per unit area is a key metric for engineering the performance of miniaturized electrochemical devices. An important new research direction for studying the electrical double-layer capacitance of graphene is to investigate the capacitance per unit area with the aid of graphene electronic band structure. Inspired by this new research direction, the proposed research explores a new paradigm for precise engineering of the electrical double-layer capacitance of miniaturized graphene electrochemical devices. This paradigm involves enhancing the correlation between electrons in graphene and ions in the electrolyte. The research approach in this study is interdisciplinary in that it will use advanced van der Waals graphene heterostructures from quantum physics to explore a longstanding question in electrochemistry. Specifically, van der Waals graphene heterostructures will be used as the test device structure, where the potential profile across graphene will be tuned during the construction of the heterostructure. To study the effect of the potential profile in graphene on the electrical double-layer capacitance, the devices will be electrically characterized using capacitance-voltage and voltammetry measurements. The proposed research project may enable accurate engineering of the capacitance in graphene with nanoscale precision, while revealing a pathway for increasing its achievable value beyond the current limits. This project will also trai of students in important scientific areas and provide them with expertise in device physics, nanofabrication, and analysis methods.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.