The superlative electronic, optical, mechanical, and chemical properties of graphene suggest broad technological opportunities for graphene-based materials and composites. However, the transition from the research laboratory to widespread commercial utilization requires economical methods for the mass production of graphene and graphene-based materials. Among the emerging methods for synthesizing graphene, solution-based processing holds particular promise because of its low cost, high throughput, chemical versatility, and scalability to large quantities. Furthermore, solution-processed graphene can be seamlessly integrated with other nanomaterials or polymers to yield composites for a wide array of applications such as energy conversion and storage, catalysis, electronics, and high-strength materials. This article highlights the range of techniques being developed for processing graphene in solution with a specific emphasis on solution-based methods for realizing graphene-based composites. In addition to fundamental principles, representative applications for these materials are presented.
