Large-scale synthesis of graphene and other 2D materials towards industrialization

Abstract

The effective application of graphene and other 2D materials is strongly dependent on the industrial-scale manufacturing of films and powders of appropriate morphology and quality. Here, we discuss three state-of-the-art mass production techniques, their limitations, and opportunities for future improvement.

Fig. 1. Specific target-oriented techniques for the mass production of 2D materials.

2D films and heterostructures require high crystal quality and homogeneous thickness for applications such as electronics and spintronics, whereas high-porosity powders with vast specific surface area can be used in contexts such as catalysts and energy storage.

Fig. 2. Historical landmarks in the development of three representative synthesis techniques.

Lefthand panels show timelines of milestones for a chemical vapor deposition (CVD), b liquid exfoliation, and c wet chemical synthesis methods. The abbreviations correspond to: metal-organic CVD (MOCVD), graphene (Gr), graphite oxide (GO), reduced GO (rGO), and molybdenum disulfide (MoS₂). Righthand panels show the corresponding strengths and weaknesses of these methods in terms of mass production (MP), thickness controllability (THK), temperature variation (TEMP), uniformity (UNI), material diversity (MAT), crystal quality (QLTY), morphology (MORPH). Panel a reprinted from refs. ^,, American Association for the Advancement of Science, ref. , Nature, refs. ^,,, Wiley, ref. , American Institute of Physics, ref. , Royal Society of Chemistry, and ref. , World Scientific. Panel b reprinted from refs. ^,, American Association for the Advancement of Science, refs. ^,, Wiley, refs. ^–, Elsevier, and ref. , Institute of Electrical and Electronic Engineers. Panel c reprinted from ref. , Elsevier, ref. , American Chemical Society, ref. , Elsevier, and ref. , Royal Society of Chemistry.

Fig. 3. Current challenges in the mass production of 2D materials.

a Single-crystal homo/heteroepitaxial growth, wrinkle formation by thermal expansion coefficient mismatch between 2D materials and growth substrates, and cracking/contamination during the transfer process are all issues presented by the CVD technique. b Inhomogeneous size and thickness of 2D nanosheets and poor production yield are problems associated with liquid exfoliation. c Low durability and instability of 2D materials by defects and environmental pollution remain challenges for wet chemical synthesis.