2D Materials for Gas Sensing Applications: A Review on Graphene Oxide, MoS2, WS2 and Phosphorene

Abstract

After the synthesis of graphene, in the first year of this century, a wide research field on two-dimensional materials opens. 2D materials are characterized by an intrinsic high surface to volume ratio, due to their heights of few atoms, and, differently from graphene, which is a semimetal with zero or near zero bandgap, they usually have a semiconductive nature. These two characteristics make them promising candidate for a new generation of gas sensing devices. Graphene oxide, being an intermediate product of graphene fabrication, has been the first graphene-like material studied and used to detect target gases, followed by MoS2, in the first years of 2010s. Along with MoS2, which is now experiencing a new birth, after its use as a lubricant, other sulfides and selenides (like WS2, WSe2, MoSe2, etc.) have been used for the fabrication of nanoelectronic devices and for gas sensing applications. All these materials show a bandgap, tunable with the number of layers. On the other hand, 2D materials constituted by one atomic species have been synthetized, like phosphorene (one layer of black phosphorous), germanene (one atom thick layer of germanium) and silicone (one atom thick layer of silicon). In this paper, a comprehensive review of 2D materials-based gas sensor is reported, mainly focused on the recent developments of graphene oxide, exfoliated MoS2 and WS2 and phosphorene, for gas detection applications. We will report on their use as sensitive materials for conductometric, capacitive and optical gas sensors, the state of the art and future perspectives.

Black Phosphorus All‐Fiber Sensor for Highly Responsive Humidity Detection

“…For instance, graphene has been used to produce distinct response upon exposure to different vapor molecules, justifying a versatile ability to sense vapors of different chemicals with high sensitivity and rapid response speed . In addition, transition metal dichalcogenides (TMDs), such as MoS 2 , WSe 2 , and WS 2 , have also been coupled to various semiconductor‐based devices, leading to decent sensing performance in terms of selectivity, sensitivity, and stability . These pioneering works have exhibited the importance of 2D materials as active sensing materials for vapor/gas sensors and aroused extensive efforts to explore alternative materials for further advancing the sensing performance.…”

“…[5] In addition, transition metal dichalcogenides (TMDs), such as MoS 2 , WSe 2 , and WS 2 , have also been coupled to various semiconductor-based devices, leading to decent sensing performance in terms of selectivity, sensitivity, and stability. [6][7][8][9] These pioneering works have exhibited the importance of 2D materials as active sensing materials for vapor/gas sensors and aroused extensive efforts to explore alternative materials for further advancing the sensing performance.The advent of 2D black phosphorus (BP) offers an opportunity. First, in contrast to other 2D materials, the layered BP possesses higher molecular adsorption energy and a larger surface-to-volume ratio, which can maximize the adsorption effect of chemicals.…”

Chemically functionalized graphene oxide thin films for selective ammonia Gas sensing

“…Functionalizations not only boost the physiochemical characteristics but also enhances the electrical, mechanical, thermal and dispersion properties of GO [47,48]. Many research groups have worked on the molecular adsorption of gas molecules on the GO surface and find out that residual oxygen or oxygen containing groups provide the active defects sites through reduction and modification of GO surface and therefore leads to the enhanced sensor response [49][50][51]. Several groups reported the change in structure and characteristics of GO after functionalization.…”

A Langasite Crystal Microbalance Coated with Graphene Oxide-Platinum Nanocomposite as a Volatile Organic Compound Sensor: Detection and Discrimination Characteristics

“…Hence, it is of paramount importance to be able to sense these VOC molecules when present in the environment. The sensing of VOCs plays a critical role in various fields such as medical diagnostics, food quality control, environmental surveillance, and explosives detection [1,2]. It is simply insufficient to be able to sense the VOC molecules; it is even more significant to distinguish the VOC molecule types as they have similar physical and chemical properties.…”

“…The contemporary increase in the popularity of two-dimensional (2D) materials has led to extensive research and development of selective detection of VOC molecules by applying the former as the sensing material [2]. The tremendous attention given to 2D materials, particularly graphene and its derivatives, is attributed to their fascinating yet peculiar properties [9].…”