Direct laser printing of graphene oxide for resistive chemosensors
Abstract This work presents the pulsed laser printing of graphene oxide, and a subsequent thermal reduction step, aiming towards the fabrication of a chemical sensor device that operates at room temperature. Laser printing was performed using the Laser Induced Forward Transfer technique, which enables for the rapid and highly resolved deposition of liquid and solid phase materials, while printing conditions were also studied, in terms of optimum laser fluence regime and donor receiver substrates distance, so as to avoid undesirable satellite debris, which has detrimental effects on the sensor performance such as adjacent sensor cross talk, etc. The evaluation of the reduction efficiency was made by Fourier Transform Reflectance spectroscopy and electrical characterization of the thermally reduced devices. Finally, the response of the sensor upon exposure to water vapors is evaluated, and sensitivities down to 0.22%%RH were recorded.