Abstract
In this work, gas sensors based on laser reduction of graphene oxide (GO) have
been fabricated and studied. Chemico-physical structure of the prototypes sensor were
characterized by Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS) and
four-point contact measurements to determine sheet resistance. Furthermore, gas sensing
properties of the prototypes exposed to 10 ppm to 100 ppm of ethanol and 25 ppm to 130
ppm of ammonia were studied. The results show that the devices present a first-order low
pass filter electrical impedance response, with virtually zero phase up to 100 kHz being
the behaviour purely resistive. The sensitivity increases as the gas concentration increases
being of 0.0402 ± 0.001[%/ppm] for the case of ammonia and 0.0140 ± 0.001[%/ppm] for
the case of ethanol achieved at 100 mW of laser power for rGO reduction. These results
outperform existing ones stablishing a better balance in terms of sensitivity, linearity and
technology sustainability but especially show the potential of laser reduced GO for lowcost
and low-energy gas detection.