Reduced graphene oxide for room-temperature gas sensors

Abstract

We demonstrated high-performance gas sensors based on graphene oxide (GO) sheets partially reduced via low-temperature thermal treatments. Hydrophilic graphene oxide sheets uniformly suspended in water were first dispersed onto gold interdigitated electrodes. The partial reduction of the GO sheets was then achieved through low-temperature, multi-step annealing (100, 200, and 300 degrees C) or one-step heating (200 degrees C) of the device in argon flow at atmospheric pressure. The electrical conductance of GO was measured after each heating cycle to interpret the level of reduction. The thermally-reduced GO showed p-type semiconducting behavior in ambient conditions and was responsive to low-concentration NO2 and NH3 gases diluted in air at room temperature. The sensitivity can be attributed mainly to the electron transfer between the reduced GO and adsorbed gaseous molecules (NO2/NH3). Additionally, the contact between GO and the Au electrode is likely to contribute to the overall sensing response because of the adsorbates-induced Schottky barrier variation. A simplified model is used to explain the experimental observations.

A 3D Chemically Modified Graphene Hydrogel for Fast, Highly Sensitive, and Selective Gas Sensor

“…The adsorption of trace amounts of gas molecules on Gr surface causes significant charge transfer between Gr and gas molecules, resulting in a noticeable conductance change of Gr 5, 11. Since the pioneering work reported the capability of Gr to detect a single NO 2 molecule,12 Gr materials fabricated via various strategies, such as mechanical exfoliation,12, 13, 14 chemical vapor deposition,1, 9, 15, 16 epitaxial growth,17 and chemically18, 19, 20, 21 or thermally22 reduced graphene oxide (RGO) have been exploited for gas sensing. Among them, RGO has attracted widespread attention for this purpose due to the low cost and high yield in production, and the convenience of modifying it with functional groups or doping atoms to tailor its gas sensing properties 19, 23.…”

Room-Temperature Humidity Sensing Using Graphene Oxide Thin Films

“…Lu et al demonstrated using thermally-reduced graphene oxide to fabricate high-performance sensors to detect NO 2 and NH 3 in air [10] [11]. Lange et al used a graphene-palladium nanoparticle composite to detect hydrogen in air [12].…”

Effective adsorption and collection of cesium from aqueous solution using graphene oxide grown on porous alumina

“…[1][2][3][4][5][6][7] The low cost and high chemical stability of graphene make its use feasible for largescale applications. However, pristine graphene without any chemical modifications shows a hydrophobic nature, and hence it is difficult for graphene to adsorb ion species in aqueous solutions.…”