High yield synthesis of single-layer graphene microsheets with dimensional control

Future composite applications will require dimensional control of graphene microsheets (GMs) to optimize structure and performance. However, realizing this goal in a high yield, cost-effective manner is presently a major challenge. We here demonstrate a simple approach to prepare single-layer GMs with a yield of >90% by one-step hydrothermal treatment of graphene oxide sheets. The addition of poly(vinyl pyrrolidone) is critical for producing single-layer GMs with specific sheet sizes and does not significantly affect the hydrothermal cutting of GMs. Using hydrothermal treatment under different conditions, the lateral dimensions of the single-layer GMs can be tuned to yield specific surface areas over a range of ∼3.5 orders of magnitude, from 30 to 9 × 10−3 μm2.