Solution dispersed 2D graphene & MoS2 for an inkjet printed biocompatible photodetector

Two-dimensional (2D) layered materials have shown promise for a wide range of semiconducting devices which can be formed not only on rigid Si substrates but also low-cost, flexible and biocompatible substrates. In this paper, we have tested the biocompatibility of various 2D materials, such as graphene and MoS
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in several organic solvents. Specifically, these materials have been dispersed in Isopropyl Alcohol (IPA), a mixture of Cyclohexanone/Terpineol with a 7∶3 ratios (C/T), and N-Methyl-2-pyrrolidone (NMP). The electrical properties were characterized of all drop cast solutions. For preliminary analysis of the electrically-conducting dispersions of graphene and MoS
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, the solutions were drop cast onto thin, flexible and polyethylene terephthalate (PET) and polyimide films. Mouse embryonic fibroblast cells (STOs) were used to perform biocompatibility assays. Optical microscopy was used to gauge the degree of biocompatibility of all of the formulated dispersions. We also highlighted an inkjet printed photodetector which can be considered as a future possibility for in vivo photo sensing applications.