Sol-Gel Production of Semiconductor Metal Oxides for Gas Sensor Applications

Abstract

As they are widely utilized in industries including the food packaging industry, indoor air quality testing, and real-time monitoring of man-made harmful gas emissions to successfully combat global warming, reliable and affordable gas sensors represent enormous market potential. For environmental monitoring, chemical safety regulation, and many industrial applications, the detection of carbon monoxide (CO), carbon dioxide (CO2), nitrogen dioxide (NO2), and methane (CH4) gases is essential. To reliably and quantitatively detect these gases, much-improved materials and methods that are adaptable to various environmental factors are needed using low-cost fabrication techniques such as sol–gel. The advantages of employing metal oxide nanomaterials-based chemoresistive for creating high-performance gas sensors are shown by key metrics such as selectivity, sensitivity, reaction time, and detection. The primary sensing methods are also grouped and thoroughly covered. In light of the current constraints, anticipated future developments in the field of sol–gel nanomaterial-based chemoresistive gas sensors are also highlighted.

Recent advances in the synthesis of ZnO-based electrochemical sensors

“…In addition, it has been found that defects and internal stress can broaden the XRD peak, so the actual value of crystallite size is higher than the average size calculated with Scherer's formula [48,49]. Nanomaterials-based zinc oxide has some advantages such as high sensitivity and selectivity, lower time, and accurate detection [50]. In another research, the combination of sol-gel synthesis for nucleation and hydrothermal preparation for growing zinc oxide nanorods on a polyethylene terephthalate substrate coated with tin oxide has been successfully applied to fabricate a wurtzite hexagonal structure in nanoscale (entire process under 100 °C) [51].…”