MXene Inks for High-Throughput Printing of Electronics

MXene inks are promising alternatives for conventional conductive inks in printing electronics. However, the formulation of MXene inks is challenging due to the physicochemical properties of the few solvents in which MXenes can be dispersed. Furthermore, conventional MXene dispersions form high-viscosity gels at low concentrations, making their ink formulation even more difficult. Here, a novel co-solvent-based approach is reported for dispersing MXenes in polar organic solvents that have excellent physicochemical properties as a carrier solvent for ink formulation but are not suitable for dispersing MXenes. Water is used as a dispersing agent and the second component of the co-solvent system. The surfactant-like role of water in dispersing MXenes in such solvents is also confirmed using molecular dynamics simulations. Using this strategy, the sol-gel transition is significantly upshifted, enabling the formulation of highly concentrated inks with single- or few-layered large-flake MXenes. Numerous types of electronic components such as interconnects, resistors, transparent flexible conductive electrodes, and micro-supercapacitors are fabricated using high-throughput coating and printing techniques such as gravure printing, showcasing the immense potential of MXene inks for room-temperature printing of electronics.|While water is a good solvent for dispersing MXenes, high-throughput printing of water-based dispersions typically yields poor results. Excellent ink properties are achieved in co-solvent systems such as propylene glycol and water, whereby water plays the role of a surfactant to disperse MXenes in solvents well known for their suitability as carrier medium for various printing techniques. image