Paper 2D+EM+MI+NS-MoM4
Semiconducting WS₂ and h-BN Inks for Printing Optically-active Nanodevices

Monday, October 21, 2019, 9:20 am, Room A216

We present our work on dispersions of WS₂ and h-BN using cyclohexanone and terpineol (C/T) as the solvent to subsequently print prototype nanodevices. Current-voltage measurements, Raman spectroscopy, and photoluminescence spectroscopy were used to characterize the properties of these inks produced by various sonication techniques such as horn tip sonication, magnetic stirring and shear mixing. Both photodetector and capactive heterostructure devices were formed with these materials. From this analysis, the photoresponsivity and detectivity of the graphene-WS₂-graphene heterostructure devices were calculated to be ~ 0.86 A/W and ~ 10¹³ J, respectively. Capacitance-voltage (C-V) and C-frequency (f) measurements were also conducted, where the V was swept from – 6 V to + 6 V, while the change in C was measured from f ~ 20 kHz up to 3 MHz to gain insights into the nature of the graphene-WS₂ interface. An all-inkjet-printed graphene-h-BN-graphene capacitors were fabricated and leakage current density, J_Leakage, of up to ~ 0.072 µA/mm² and capacitance density of up to ~ 2.4 µF/cm² is reported. Finally, the influence of temperature, frequency, and LED illumination on the performance of the graphene-h-BN-based capacitor is explored with the help of capacitance density-voltage measurements at different parameters to promote the all-inkjet-printed capacitor for photosensitive detector applications.