Hydrogen gas sensor based on metal oxide nanoparticles decorated graphene transistor

Abstract

In this work, in order to enhance the performance of graphene gas sensors, graphene and metal oxide nanoparticles (NPs) are combined to be utilized for high selectivity and fast response gas detection. Whether at the relatively optimal temperature or even room temperature, our gas sensors based on graphene transistors, decorated with SnO2 NPs, exhibit fast response and short recovery times (∼1 seconds) at 50 °C when the hydrogen concentration is 100 ppm. Specifically, X-ray photoelectron spectroscopy and conductive atomic force microscopy are employed to explore the interface properties between graphene and SnO2 NPs. Through the complimentary characterization, a mechanism based on charge transfer and band alignment is elucidated to explain the physical originality of these graphene gas sensors: high carrier mobility of graphene and small energy barrier between graphene and SnO2 NPs have ensured a fast response and a high sensitivity and selectivity of the devices. Generally, these gas sensors will facilitate the rapid development of next-generation hydrogen gas detection.

Two-Dimensional Materials for Sensing: Graphene and Beyond

“…They observed an increase in output current with increase in H2 concentration from 1 ppm to 100 ppm with good reproducibility (as shown in Figure 5b). The achieved lowest resolution limit of 1 ppm proves the potential of SnO2 NP-graphene for high sensitive low level detection of H2 gas [131].…”

“…Apart from dopants and defects, other chemical functionalization methods such as modification with metal and metal oxide nanoparticles (NPs) and polymers have also been studied. Compared to pristine graphene and rGO, sensors based on graphene/rGO modified with nanoparticles of metals or metal oxides have demonstrated highly sensitive and selective sensing behavior [128][129][130][131][132][133][134][135], which could be attributed to large changes in the electronic properties of graphene/rGO upon gas exposure due to the synergistic effects of NPs and graphene/rGO.…”

“…Recently, gas sensors based on graphene transistors decorated with SnO2 NPs exhibited high selectivity, fast response and short recovery (~1 s) to 100 ppm H2 at 50 °C (as shown in Figure 5a-c) [131]. FETs based on graphene decorated with metal oxide NPs were employed for developing high performance hydrogen gas sensors.…”

Changes in work function due to NO2 adsorption on monolayer and bilayer epitaxial graphene on SiC(0001)

“…Instead, graphene must be either grown or deposited on a supporting substrate-ideally one that is compatible with Si-based technologies, such as SiO 2 or SiC. However, the interaction between graphene and a substrate can have a significant influence on both the structural and electronic properties of graphene and any material adsorbed or deposited on it [6,7].…”

“…Resistance measurements provide a highly sensitive means of determining the presence of molecular adsorbants on a graphene surface. Ensuring selectivity towards a particular molecule is more challenging, but can be achieved by functionalizing the surface with metallic dopants [1,2] or by analyzing the low-frequency noise after molecular adsorption [3]. Graphene-based NO 2 sensors have been shown to detect concentrations below 1 part per billion (ppb) [4,5].…”