Abstract Printed electronics is attracting a great deal of attention in both research and commercialization as it enables fabrication of large‐scale, low‐cost electronic devices on a variety of substrates. Printed electronics plays a critical role in facilitating widespread flexible electronics and more recently stretchable electronics. Conductive nanomaterials, such as metal nanoparticles and nanowires, carbon nanotubes, and graphene, are promising building blocks for printed electronics. Nanomaterial‐based printing technologies, formulation of printable inks, post‐printing treatment, and integration of functional devices have progressed substantially in the recent years. This review summarizes basic principles and recent development of common printing technologies, formulations of printable inks based on conductive nanomaterials, deposition of conductive inks via different printing techniques, and performance enhancement by using various sintering methods. While this review places emphasis on conductive nanomaterials, the printing techniques and ink formulations can be applied to other materials such as semiconducting and insulating nanomaterials. Moreover, some applications of printed flexible and stretchable electronic devices are reviewed to illustrate their potential. Finally, the future challenges and prospects for printing conductive nanomaterials are discussed. 
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                            Inkjet‐printed flexible MXetronics : Present status and future prospects
                        
                    
    
            Abstract Over the past several years, atomically thin two‐dimensional carbides, nitrides, and carbonitrides, otherwise known asMXenes, have been expanded into over fifty material candidates that are experimentally produced, and over one hundred fifty more candidates that have been theoretically predicted. They have demonstrated transformative properties such as metallic‐type electrical conductivities, optical properties such as plasmonics and optical nonlinearity, and key surface properties such as hydrophilicity, and unique surface chemistry. In terms of their applications, they are poised to transform technological areas such as energy storage, electromagnetic shielding, electronics, photonics, optoelectronics, sensing, and bioelectronics. One of the most promising aspects ofMXene'sfuture application in all the above areas of interest, we believe, is reliably developing their flexible and bendable electronics and optoelectronics by printing methods (henceforth, termed asprinted flexible MXetronics). Designing and manipulatingMXeneconductive inks according to the application requirements will therefore be a transformative goal for future printed flexible MXetronics.MXene'scombined property of high electrical conductivity and water‐friendly nature to easily disperse its micro/nano‐flakes in an aqueous medium without any binder paves the way for designing additive‐free highly conductiveMXene ink. However, the chemical and/or structural and hence functional stability of water basedMXeneinks over time is not reliable, opening research avenues for further development of stable and conductiveMXeneinks. Such priorities will enable applications requiring high‐resolution and highly reliable printedMXeneelectronics using state‐of‐the art printing methods. EngineeringMXenestructural and surface functional properties while tuningMXeneink rheology in benign solvents of choice will be a key for ink developments. This review article summarizes the present status and prospects ofMXeneinks and their use in inkjet‐printed (IJP) technology for future flexible and bendableMXetronics. 
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                            - Award ID(s):
- 1935676
- PAR ID:
- 10490122
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Applied Research
- ISSN:
- 2702-4288
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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