Solution-Processed 2D Materials for Electronic Applications

Toward practical demonstration of high-quality two-dimensional (2D) nanomaterial-based electronics, solution-based processing has been considered as a promising route of scalable synthesis for more than a decade due to the capability of mass production without process complexity. However, in the earlier stage, solution-processed 2D nanomaterials were not desirable for scalable electronic applications due to their structural limitations including a small lateral dimension and polydispersity in thickness, which hinder formation of electronically active percolated thin-film networks. To overcome this limitation, various strategies have been reported including isopycnic density gradient ultracentrifugation to minimize thickness distribution and alkali-metal intercalations to increase exfoliation yield. Along this line, molecular intercalation-based electrochemical exfoliation has been reported as an emerging solution-based approach by resolving the well-known limitations of conventional solution processing. The resulting 2D nanomaterials with highly desired morphologies can be successfully utilized to form electronically active ultra-thin-film networks over a large area, and thus, gate-tunable thin-film electronics can be achieved with decent device performance. In this Spotlight article, we provide a chronological introduction of solution-based processing of 2D nanomaterials and their applications in electronics. Also, we discuss the remaining challenges and opportunities of solution-based processing of 2D nanomaterials for electronics.