Current Applications of Gas Sensor Based on 2-D Nanomaterial: A Mini Review

Abstract

Gas sensor, as one of the most important devices to detect noxious gases, provides a vital way to monitor the concentration and environmental information of gas in order to guarantee the safety of production. Therefore, researches on high sensitivity, high selectivity, and high stability have become hot issues. Since the discovery of the nanomaterial, it has been increasingly applied to the gas sensor for its distinguishing surface performances. However, 0-D and 1-D nanomaterials, with limited electronic confinement effect and surface effect, cannot reach the requirement for the production of gas sensors. This paper gives an introduction about the current researching progress and development trend of 2-D nanomaterials, analyzes the common forms of 2-D nanoscale structure, and summarizes the mechanism of gas sensing. Then, widely concerned factors including morphological properties and crystalline structure of 2-D nanomaterial, impact of doped metal on the sensibility of gas sensors, impact of symmetry, and working temperature on the selectivity of gas sensors have been demonstrated in detail. In all, the detailed analysis above has pointed out a way for the development of new 2-D nanomaterial and enhancing the sensibility of gas sensors.

Current Trends in Nanomaterials for Metal Oxide-Based Conductometric Gas Sensors: Advantages and Limitations. Part 1: 1D and 2D Nanostructures

“…Studies have shown that in addition to traditional layered 2D nanomaterials such as graphene, black phosphorus or phosphorene, silicene, borophene, boron nitride, and transition metal dichalcogenides (TMDs), metal oxides may also have 2D structures [351,355]. It was established that some metal oxides such as Ga 2 O 3 and metal trioxides with a general formula of MO 3 (M = Mo, Ta, W, etc.)…”

“…Currently, based on these 2D nanomaterials, a large number of prototypes of gas sensors have been made, which have increased sensitivity to various gases. An analysis of these results can be found in numerous reviews devoted to the consideration of these materials [323,326,334,345,[347][348][349][350][351][352][353][354].…”

Fluorescent lamp tungsten filament thermionic emission gun as a novel humidity optical sensor

“…For many years, how to measure and monitor the relative humidity (RH) amount has been a matter of debate in different industries, agriculture, and social health [1][2][3] . For examples, nano-based gas sensors provide signi cant approach to assess the concentration and environmental information of gases 4,5 . In fact, these sensors comprise of a transducer and an active layer to convert the chemical information into another form of electrical signal gradients like frequency, current, voltage, etc.…”

Nanomaterial-Based CO2 Sensors

“…The use of nanomaterials has been shown to improve traditional sensing techniques in terms of sensitivity, stability, response time, and selectivity [ 18 ]. The aforementioned benefits of nanomaterials are often ascribed to their high surface to volume ratio, high surface energy, quantum size effect, and high electron conductivity [ 19 ].…”