چكيده به لاتين
In recent decades, sensor technology has been widely used and studied for gas detection. Due to the different applications of these sensors and the inherent limitations of gas measurement technology, researchers have studied various methods to improve the performance of gas sensors. Certain types of conductive materials change their electrical resistance in response to interactions with gases and vapors, and their sensors are known as Chemiresistors.
Recent methods in this field are based on the use of metal oxide nanomaterials, polymers, and their combinations to build the enhanced chemiresistores. Among the types of conductive polymers (CP), polypyrrole (PPy) is prominent due to its special properties such as excellent oxidation activity, biocompatibility, low toxicity, adjustable electrical conductivity, and good environmental stability. In order to improve the performance of PPy-based gas sensor properties, its composite nanomaterials have been investigated. The use of a variety of oxidized metal nanostructures can improve the sensory properties of composite nanomaterials. Among these oxides, due to their special properties, the sensory properties of zinc oxide (ZnO) nanostructures have been extensively investigated. ZnO has the potential for automated growth to produce nanostructures of various shapes, sizes, and morphologies. In this study, the properties of gas sensors based on ZnO-PPy nanocomposites for the fabrication of chemical resistors have been investigated. The structure of these sensors, the basis of design, manufacturing methods, and applications of resistive gas sensors are introduced.
Zinc oxide particles with nanotube and nanosheet structures were synthesized electrochemically and the effect of its composition on the sensory properties of polypyrrole was investigated. It has been observed that the use of zinc oxide improves the sensitivity of the sensor to measure ammonia. The detection limit of the sensor for determining ammonia was 16 ppb, it had high immunity to humidity. selectivity tests showed that the introduced Point of Care (POC) device is unique and even 90% humidity does not pose a problem for measuring ammonia.
