Ambient Processing and Patterning of Graphene Oxide across Multiple Length Scales

氧化石墨烯是一种原子薄的材料，具有一系列独特的可调性质，在柔性电子、储能、传感器、复合材料和生物医学工程中具有广阔的应用前景。氧化石墨烯的多功能性在于它的结构包括连接到底层碳原子晶格上的氧原子和不连接氧原子的区域。当氧原子被移除时，氧化石墨烯的电学、光学和化学性质都会发生巨大的变化。然而，标准的除氧方法涉及剧毒化学物质或暴露在潮湿和无氧环境中的高温下，这些条件不适合大规模生产。该奖项将发展所需的基础知识，通过一种环境友好且易于实施的过程，以前所未有的空间控制选择性地调节氧化石墨烯的氧含量。这些能力将使氧化石墨烯能够广泛集成到能源、医疗保健、电子和交通技术的设备中，从而造福社会。该项目的教育部分将通过实践纳米材料主题活动促进贫困中学生对科学的兴趣，并通过参与实验室参观和研究在高等教育水平上保持对科学的兴趣。电压诱导氧化石墨烯还原提供了一种调节氧化石墨烯的性质并在环境条件下将不同功能图案化成氧化石墨烯的方法。目前，人们对该过程的动力学、机理和极限以及所得到的材料的性质知之甚少。这一奖项将有助于对这种新的还原方法的加工、结构和电气功能之间的联系有基本的了解。纳米探针引发的还原将被用于确定基于电压的还原的空间分辨率极限和动力学，同时为研究还原的石墨烯氧化物中的纳米尺度尺寸效应提供平台。将基于电压的还原扩展到介观和宏观长度尺度，将使所得到的材料的化学结构和电输运表征成为可能，并阐明电压诱导还原作为大规模制造工艺的可行性。

Graphene oxide is an atomically-thin material with a unique set of tunable properties, making it promising for applications in flexible electronics, energy storage, sensors, composite materials, and biomedical engineering. The versatility of graphene oxide lies in its structure that includes regions with and without oxygen atoms attached to the underlying carbon atom lattice. When oxygen atoms are removed, the electrical, optical, and chemical properties of graphene oxide are dramatically altered. Standard methods for oxygen removal, however, involve highly toxic chemicals or exposure to high temperatures in humidity- and oxygen-free environments, conditions that are not amenable to large-scale manufacturing. This award will develop the fundamental knowledge needed to selectively tune the oxygen content of graphene oxide with unprecedented spatial control through an environmentally benign and easily implemented process. Such capabilities will benefit society by enabling the widespread integration of graphene oxide into devices for energy, healthcare, electronics, and transportation technologies. The educational component of the project will promote interest in science among disadvantaged middle school students though hands-on nanomaterials-themed activities, and sustain interest in science at higher education levels through participation in laboratory tours and research.Voltage-induced graphene oxide reduction offers a means of tuning the properties of graphene oxide and patterning heterogeneous functionalities into graphene oxide sheets and films under ambient conditions. At present, little is known about the kinetics, mechanisms, and limits of the process or the properties of the resulting material. This award will help gain fundamental insights into the links between processing, structure, and electrical function for this new reduction method. Nanoprobe-initiated reduction will be used to determine the spatial resolution limits and kinetics of voltage-based reduction, while providing a platform for investigating nanoscale size-effects in reduced graphene oxide. The extension of voltage-based reduction to mesoscopic and macroscopic length scales will enable chemical structure and electrical transport characterization of the resulting material and elucidate the viability of voltage-induced reduction as a large-scale manufacturing process.