Pre-reduction of graphite oxide as an efficient strategy for enhanced purification efficiency, product quality, and performance

The purification efficiency of graphite oxide (GTO) suspension and the lateral size of its exfoliated products are critical bottlenecks in the industrial production and practical application of graphene-based materials. Herein, a facile pre-reduction strategy using ascorbic acid as a mild reductant was proposed to improve the purification efficiency of GTO suspension and lateral size of its exfoliated products. The partial removal of labile C–O functional groups effectively inhibited the osmotic swelling and water-blocking behavior of the GTO sheets, resulting in a substantially enhanced purification efficiency. The pre-reduction treatment also repaired structural defects on the basal plane of the carbon skeleton, thus restraining sheet fragmentation and increasing the lateral size of the exfoliated products. Consequently, the carbonized graphene-based film assembled with a large-size and high-crystallinity graphene oxide component exhibited excellent mechanical, electrical, and thermal performances. Therefore, this study provides a combined process and product engineering strategy for industrial production and high-value application of graphene derivatives.