Defect-free and water based 2D material inks for printed electronics*

Solution processing of 2D materials [1] allows simple and low-cost techniques, such as ink-jet printing, to be used for fabrication of heterostructure-based devices of arbitrary complexity. However, the success of this technology is determined by the nature and quality of the inks used.
In my group we have developed highly concentrated, defect-free, printable and water-based 2D crystal formulations, designed to provide optimal film formation for multi-stack fabrication [2]. I will give examples of all-inkjet printed heterostructures, such as large area arrays of photosensors on plastic [2], programmable logic memory devices [2], capacitors [3] and transistors on paper [3,4]. Furthermore, inkjet printing can be easily combined with materials produced by chemical vapor deposition, allowing simple and quick fabrication of complex circuits on paper, such as high-gain inverters, logic gates, and current mirrors [5]. The inks are also suitable for printing onto new flexible substrates that show superior mechanical properties compared to paper, by allowing fabrication of highly resilient devices to long-lasting strain [6].

[1] Coleman et al, Science 331, 568 (2011)
[2] McManus et al, Nature Nano, 12, 343 (2017)
[3] Worsley et al, ACS Nano, 2018, DOI: 10.1021/acsnano.8b06464
[4] Lu et al, ACS Nano, 13, 11263 (2019)
[5] Conti et al, Nature comm, 11, 1, 2020
[6] Worsely et al, under review