Two‐Dimensional Nanomaterials for the Development of Efficient Gas Sensors: Recent Advances, Challenges, and Future Perspectives

Abstract

The advancement of nanotechnology has produced a huge potential to prepare highly sensitive and portable sensors with low cost and low energy consumption. Here, a comprehensive review of the recent development of two‐dimensional nanomaterials for gas sensors is presented. Emerging kinds of two‐dimensional nanomaterials‐based sensors with high surface‐to‐volume ratio and porous nanostructures are considered superior for the adsorption of gas molecules, for various gases have been discussed in this review. In addition, strategies that can enhance sensor performance by nanomaterials design and synthesis are also discussed and elaborated for the novel two‐dimensional nanomaterials to the development of sensing technology. Finally, the current challenges have been summarized and future perspectives for the development of gas sensors are also suggested.

2D materials: increscent quantum flatland with immense potential for applications

“…However, detecting the gas/VOCs at ppb level in a varying humidity atmosphere is extremely challenging. There is a dire need to develop sensing materials that are highly specific and sensitive toward selective molecules even under humid conditions [ 88 ]. For real-time monitoring and industrial application, the gas sensors need to be highly responsive, selective, have low fabrication cost, and have low power consumption.…”

“…These materials have advantages and disadvantages, such as high operating temperature, low conductivity, and low surface area. 2D materials, due to their unique physical and chemical property, mechanical flexibility, and high electron mobility, are widely used for gas sensing applications [ 88 , 89 ]. The gas-sensing performance depends on various parameters such as sensitivity, selectivity, stability response/recovery time, detection limit, reproducibility, and reversibility.…”

“…The cost-effective device manufacturing technologies need to be addressed for flexible, miniaturized, and industrial-scale gas sensors [ 256 , 257 ]. The synthetic strategies which provide reasonable control over the layer thickness, defects, and composition needs to be developed to enhance the selectivity and sensitivity for optimum performance [ 88 ]. One of the significant issues with device fabrication is to make ohmic contact between 2D nanomaterials and metal contacts, as it requires sophisticated techniques and skilled labor, which indirectly sums up to increase the device cost [ 91 ].…”

Challenges and Opportunities for Printed Electrical Gas Sensors

“…Inks for the fabrication of printed electrical gas sensors typically comprise two or more of the following four components depending on the printing method used: (i) functional materials such as metallic or semiconducting nanomaterials, conductive polymers, 2D nanostructured materials, or carbon-derived materials to act as gas sensitive materials or to construct electrodes/interconnects; ,− (ii) binders such as glass powder, resins, or cellulose acetate to hold together functional particles and provide adhesion to the substrates; − (iii) solvents such as water, ethylene glycol, terpineol, or cyclohexanone to enable printability; and (iv) other additives such as wetting agents for inkjet printing as stabilizers. , The presence, type, and quantities of each component will define the rheological properties of the ink according to the requirements of the printing method. For example, inks intended for inkjet printing require low viscosities (4–30 mPa·s) to enable the formation and ejection of droplets from the nozzle(s) (<100 μm diameter) and high surface tension (20–70 dyn cm –1 ) to avoid dripping during the process.…”

Computational Design of Gas Sensors Based on V3S4 Monolayer

“…[ 1 ]. Nanomaterials show great performance in this field of technology [ 2 ]. Nowadays, the most effective materials for gas sensing belong to the groups of metal-organic framework-based nanostructured materials [ 3 , 4 ] and low-dimensional materials [ 5 , 6 ].…”