A review on recent developments and advances in environmental gas sensors to monitor toxic gas pollutants

Abstract

Air pollutants originating from various sources like vehicular emission, power stations, factories, refineries, industrial emissions, and burning of garbage in open and laboratories, include many toxic gases and pollutants like hydrogen chloride (HCl), hydrogen sulfide (H2S), and volatile organic compounds (VOCs) like benzene, toluene, xylene, and so on, ammonia (NH3), carbon‐monoxide (CO), carbon‐dioxide (CO2) and nitrogen oxides (NOx), and so on, that are constantly released into the atmosphere and continuously deteriorating our natural environment and surroundings. These pollutants create harmful effects on the ecosystem and affect human health. Though there are many devices available for monitoring these pollutants and toxic gases, they are very expensive and time‐consuming. Since the safety of the life of human health, plants, animals, and their surrounding area on topmost priority, thus there is a significant need to develop user‐friendly and environmentally friendly sensing devices for real‐time monitoring of air pollutant emissions, which are extremely hazardous to the environment, breathable air, and human health. Extensive research has been made by researchers to develop an ideal sensor suitable for the environment and which can be within the reach of the masses. This review article presents different types of gas sensors and the technologies on which they work upon. We have also discussed the different gas sensors with their principle of operation. The working, advantages, and disadvantages of each type of sensor have also been discussed and compared with each other. Despite extensive research over several years to develop a highly sensitive, selective, and quick response sensor for the detection of flammable and toxic gases, the future scope and perspective for scientists are also proposed at the end of this article.

Development and Testing of NDIR-Based Rapid Greenhouse Gas Detection Device for Dairy Farms

“…Therefore, it is necessary to monitor the greenhouse gases emitted from dairy farms, and some scholars [7,[9][10][11] have already performed research on monitoring this, but most of them use the existing gas analyzers to perform stationary monitoring, however, these are only capable of detecting the concentration of the gases in fixed locations on the dairy farms, and are unable to comprehensively detect the distribution of the concentration throughout the entire livestock and poultry farm. The traditional fixed methods for quantitative detection of multiple analytes by gas chromatographs, semiconductor gas sensors, and electrochemical sensors have limitations in real-time monitoring, response time, selectivity, and resistance to cross-talk [12,13]. The NDIR technology [14][15][16][17] has obvious advantages in the field of multi-component gas detection due to its high sensitivity, high selectivity, fast response, and long life span [18].…”

Defective Diamane: A Superior Sensor for Toxic Gases Capture and Detection with Excellent Selectivity, Sensitivity, and Reversibility at Room Temperature

“…1 Toxic gas molecules can be observed in a multitude of air pollution sources. 2 CO, as a colorless, tasteless, and odorless gas, generated by fuel combustion and industrial activity, can specifically bind to hemoglobin, leading to poisoning and oxygen deprivation in the human body. 3,4 Nitrogen oxides, such as NO and NO 2 , are the primary culprits behind acid rain, haze, and photochemical smog.…”

Thermally Inducing Viscous Fluids to Generate Co-Based Perovskites Enriched with Active Species for the Removal of VOCs

“…Volatile organic compounds (VOCs) originate from various sources such as industrial emissions, vehicle exhaust, and household products like paints and solvents. , Among VOCs, toluene is particularly harmful, as it is known to cause cancer and respiratory issues and can contribute to air pollution and smog formation, posing serious health and environmental risks. , However, the efficient removal of VOCs from various industrial and environmental sources is a pressing challenge . The common methods for VOC treatment include adsorption, catalytic oxidation, thermal oxidation, biofiltration, and solvent recovery. − Among them, catalytic oxidation offers the advantage of converting VOCs into less harmful byproducts.…”

“…Volatile organic compounds (VOCs) originate from various sources such as industrial emissions, vehicle exhaust, and household products like paints and solvents. 1,2 Among VOCs, toluene is particularly harmful, as it is known to cause cancer and respiratory issues and can contribute to air pollution and smog formation, posing serious health and environmental risks. 3,4 However, the efficient removal of VOCs from various industrial and environmental sources is a pressing challenge.…”