MXene Multifunctional Inks: a New Perspective toward Printable Energy-related Electronic Devices

Advanced ink printing techniques, such as printing and coating, have overcome the limitations of traditional manufacturing methods, allowing for rapid prototyping of films and electronic devices with sophisticated structures and specific functions. These techniques hold enormous potential in wearable smart identification, energy storage, electromagnetic shielding and absorption, touch display, and so on. The key to printing advanced energy and electronic devices lies in the development of cutting-edge functional inks and their corresponding printing technologies. MXene, a family of two-dimensional compounds composed of transition metal carbides, nitrides, or carbonitrides, was discovered in 2011. MXene exhibits remarkable physical and chemical properties, including high conductivity, pronounced hydrophilicity, and diverse surface chemistry, which has garnered significant attention within the research community and made it particularly suitable as inks in printing applications. Conducting research on the printing behavior and mechanisms of MXene inks is crucial not only for achieving high-precision patterns but also for establishing a solid foundation for manufacturing techniques that can precisely create multiscale, multimaterial and multifunctional films, and electronic devices. This article begins with a brief discussion of MXene flakes' synthesis and colloidal stability, followed by a detailed examination of its rheological characteristics, printable ink formulation, and printing methods. Additional, special attention is given to the latest advances of MXene ink in energy, health, and sensing applications. The perspective concludes with a summary of current research challenges and future directions in this area, offering new perspectives and insights for researchers.