2D-Crystal-Based Functional Inks

The possibility to produce and process graphene, related 2D crystals, and
heterostructures in the liquid phase makes them promising materials for
an ever-growing class of applications as composite materials, sensors, in
fl exible optoelectronics, and energy storage and conversion. In particular,
the ability to formulate functional inks with on-demand rheological and
morphological properties, i.e., lateral size and thickness of the dispersed 2D
crystals, is a step forward toward the development of industrial-scale, reliable,
inexpensive printing/coating processes, a boost for the full exploitation of
such nanomaterials. Here, the exfoliation strategies of graphite and other
layered crystals are reviewed, along with the advances in the sorting of lateral
size and thickness of the exfoliated sheets together with the formulation of
functional inks and the current development of printing/coating processes of
interest for the realization of 2D-crystal-based devices.