Preparation Of Graphite Oxide And Research Of Its Sensing Character For Hydrogen

Hydrogen gas is widely produced and used in our life. Detection and measurement of H2in a reliable and efficient manner is of great value in these applications, not only from safetyconcerns but also economically beneficial.Hence a simple but efficient hydrogen sensor isurgently demanded.In this work, novel chemo-resistive gas sensors based on reduced graphite oxide (rGO)thin films have been fabricated and evaluated for hydrogen detection. The rGO materials werethermally treated at various conditions and analyzed using X-ray diffraction, Fouriertransform infrared spectroscopy, and X-ray photoelectron spectroscopy techniques toinvestigate the change of functional groups. The rGO thin films were adopted as activesensing elements without any rare metal decoration, and their sensing response to hydrogenwas studied.The rGOs treated at 70°C in atmosphere (rGO070a), 200°C in a vacuum (rGO200v), and500°C in a vacuum (rGO500v) exhibited n-type, ambipolar, and p-type behavior, respectively.Even though the rGO070a exhibited very fast response and high sensitivity to 160 ppmhydrogen at room temperature, the recovery was too slow for practical use. The rGO500vexhibited good sensitivity (~3%), response time (~100 s), and recovery time (~10 s) to 160ppm hydrogen gas at room temperature.However,there are many defacts for graphite oxidation as a new hydrogen sensitivematerial, further investigations are needed to improve the stability and selectivity of this newsensor.