Two‐Dimensional Nanostructured Materials for Gas Sensing

Abstract

Two-dimensional (2D) nanostructures are highly attractive for fabricating nanodevices due to their high surface-to-volume ratio and good compatibility with device design. In recent years 2D nanostructures of various materials including metal oxides, graphene, metal dichalcogenides, phosphorene, BN and MXenes, have demonstrated significant potential for gas sensors. This review aims to provide the most recent advancements in utilization of various 2D nanomaterials for gas sensing. The common methods for the preparation of 2D nanostructures are briefly summarized first. The focus is then placed on the sensing performances provided by devices integrating 2D nanostructures. Strategies for optimizing the sensing features are also discussed. By combining both the experimental results and the theoretical studies available, structure-properties correlations are discussed. The conclusion gives some perspectives on the open challenges and future prospects for engineering advanced 2D nanostructures for high-performance gas sensors devices.

Emerging Applications of Elemental 2D Materials

“…[161][162][163] Sensors: Gas and chemical sensors based on nanomaterials (especially 2D materials) exhibit a high degree of sensitivity from their large surface to volume ratio, high room temperature mobility, subthreshold swing in FET geometries, and chemical stability. [164,165] In particular, phosphorene gas sensors have demonstrated a high degree of sensitivity and selectivity in comparison to other nanomaterial sensors. [166] Mayorga-Martinez et al fabricated a few-layer phosphorene device that proved to be selective to methanol and can detect as low as 28 ppm of methanol gas.…”

Chemoresistive materials for electronic nose: Progress, perspectives, and challenges

“…Another advantage that 2D materials provide in gas sensing is their high thermal stability and the wide range in their operating temperature . The 2D nanostructures can provide certain additional benefits, including more active sites, easier surface functionalization, better compatibility with device integration, and the possibility of being assembled in a three‐dimensional structure, and perform a crucial role in the development of high‐performance gas sensors . They are also possible to maximize the sensitivity and selectivity of the gas sensor by fabricating a hybrid structure based on a 2D material.…”

“…127 The 2D nanostructures can provide certain additional benefits, including more active sites, easier surface functionalization, 128 better compatibility with device integration, and the possibility of being assembled in a three-dimensional structure, and perform a crucial role in the development of high-performance gas sensors. 129 They are also possible to maximize the sensitivity and selectivity of the gas sensor by fabricating a hybrid structure based on a 2D material. In addition, 2D materials can easily be fabricated with chemically resistive field effect transistors (FETs) that operate with less power consumption and provide superior safety.…”

Nanoscale heterojunctions of rGO-MoS2 composites for nitrogen dioxide sensing at room temperature

“…Hence, the quest for highly sensitive NO 2 sensors with low detection limit is in the process which will enable the sensors to operate at low or room temperature. Recently graphene and its derivatives (graphene oxide, rGO) along with other transition metal dichalcogenides like MoS 2 , WS 2 etc have been studied extensively and have proved to be promising gas sensing materials because of their high surface to volume ratio and excellent electronic properties [7][8][9][10][11]. In this regard, researchers are trying to focus on developing new novel nanomaterials hybrids out of these, in order to exploit the synergistic properties and develop high performance gas sensors.…”

“…In this regard, researchers are trying to focus on developing new novel nanomaterials hybrids out of these, in order to exploit the synergistic properties and develop high performance gas sensors. Development of hybrid structures renders multiple nanoheterojunctions and interfacial electronic modulations across such heterojunctions drastically enhance the sensing performances [8,12]. For example, there can be electronic modulation of charge carriers and localised charge carrier densities resulting in modulation of Fermi level, effective charge carrier separation for efficient charge transport rendering fast and enhanced sensing [8,[12][13][14].…”