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.
