Green Synthesis of Metal Oxides Semiconductors for Gas Sensing Applications

Abstract

During recent decades, metal oxide semiconductors (MOS) have sparked more attention in various applications and industries due to their excellent sensing characteristics, thermal stability, abundance, and ease of synthesis. They are reliable and accurate for measuring and monitoring environmentally important toxic gases, such as NO2, NO, N2O, H2S, CO, NH3, CH4, SO2, and CO2. Compared to other sensing technologies, MOS sensors are lightweight, relatively inexpensive, robust, and have high material sensitivity with fast response times. Green nanotechnology is a developing branch of nanotechnology and aims to decrease the negative effects of the production and application of nanomaterials. For this purpose, organic solvents and chemical reagents are not used to prepare metal nanoparticles. On the contrary, the synthesis of metal or metal oxide nanoparticles is done by microorganisms, either from plant extracts or fungi, yeast, algae, and bacteria. Thus, this review aims at illustrating the possible green synthesis of different metal oxides such as ZnO, TiO2, CeO2, SnO2, In2O3, CuO, NiO, WO3, and Fe3O4, as well as metallic nanoparticles doping.

Biosynthesis of TiO2 nanoparticles by Caricaceae (Papaya) shell extracts for antifungal application

“…Biological technologies are used in Bio-synthesis, like usages of plant extracts; it could be a favourite to other techniques. Amongst the biologically objects stated above, plant or their extract appear to be the paramount proxies due to their simply available, appropriate for masses productions of Nanoparticles and wastes product is environmentally friendly dissimilar some micro-organismal extract 41 , 42 . Phyto constituents in plant extract can concurrently purpose as dropping agents because of the kindly and multipurpose function 43 , 44 .…”

Review on Porosity Control in Nanostructured Semiconducting Metal Oxides and Its Influence on Chemiresistive Gas Sensing

“…Among them, SMOs have been widely used as gas-sensing layers due to their superior gas sensitivity at elevated temperatures. − In particular, nanostructured materials have been actively investigated in the gas sensor . Thus far, different synthetic methods for porous nanostructured SMOs have been reported including electrospinning, ,− spray pyrolysis, hydrothermal, solvothermal, , and direct precipitation. , On the other hand, various techniques to overcome their poor intrinsic gas selectivity have been suggested including functionalization with catalysts, − defect creation, phase control, and coating with selectivity overlayer. ,, Many publications ,− summarizing the performance of state-of-the-art SMOs concerning sensitivity, selectivity, sensing mechanisms, and morphology engineering have been widely reported.…”

Theoretical validation of experimental properties of TiO2 prepared through organometallic precursors

“…[4,5] They are based on semiconductors like SnO 2 , CdO, ZnO, Co 3 O 4 , Mn 3 O 4 , WO 3 , and so forth. [6] Among them the TiO 2 material, this one gives us many possible applications such as photo-sensors for detecting UV light, [7] biosensor for detecting biological substance, [8] virologysensor for rapid detection of SARS-CoV-2 (COVID-19), [9] and gas sensor for detecting the pollutants gas. [10,11] The TiO 2 compound grows in various forms: rutile, anatase, and brookite.…”