Roya Maboudian (Advisor)

Hydrogen safety demands highly sensitive H2 sensors with rapid response (< 30 s) to detect leakage at concentrations far below its explosion limit (40,000 ppm). Nanostructured materials based on palladium (Pd) and its alloys emerged as the most promising candidates that meet the standards set by the U.S. Department of Energy for hydrogen sensors. In this study, we are developing novel robust chemiresistive gas sensors employing single-crystalline mesoporous bimetallic alloys (s-meso PdM) nanocubes (NCs) on ordered mesoporous tin (IV) oxide (m-SnO2) for remote and distributed H2 sensors...

Metal oxide semiconductors (MOX) such as SnO2 are widely used in chemiresistive gas sensors due to their high chemical and thermal stability, low cost, and tunable chemical and electronic properties. The introduction of porosity to the MOX structure enhances their gas-sensing properties by increasing the surface area available for interactions with gas molecules. This higher surface area enhances the sensor's sensitivity by providing more active sites for gas adsorption. Also, a faster response/recovery time can be obtained as gas molecules can more quickly interact with a...

Chemiresistive gas sensors based on semiconductor metal oxides, such as tin dioxide, help to identify and monitor toxic gases and pollution, and play a vital role in industrial and environmental applications. However, the interfering effect of ambient humidity is a major challenge in their reliable operation, as water molecules on the oxide surface can affect the sensitivity and other characteristics of the sensor. To address this challenge, we are modifying the sensor surface by applying thin hydrophobic layers, such as hexamethyldisilazane (HMDS), to achieve ultrahydrophobicity,...