Roya Maboudian (Advisor)

Long-term stability of chemiresistive gas sensors is essential for their use in industrial and residential safety and air-quality monitoring systems. Incorporation of noble metals into the gas sensors has been proved to be an effective strategy to enhance their sensitivity and selectivity. However, noble metal particles are prone to poisoning, resulting in catalyst deactivation. Atomically dispersed supported metal catalysts constitute a new class of materials that contains isolated individual atoms or synergistically coupled few-atom ensembles dispersed on, and/or coordinated with...

CO2 Monitoring Inside of a Car Cabin

Young children trapped in a car without adult supervision may suffer life-threatening complications such as hyperthermia and heat stroke from extreme temperatures—which may rise to 130 °F in some cases. Our research aims to ascertain child presence within two to three minutes of unsupervised activity by probing increases in the levels of carbon dioxide emitted during human exhalation. Non-dispersive infrared (NDIR) sensors are employed to measure car carbon dioxide concentrations every two seconds. Specific numerical metrics are then...

A classic challenge in gas sensing is the tunability of the sensing material for the selective absorption of target gases without interference from unwanted species. Metal-organic frameworks (MOFs), made up of metal-cluster nodes connected by organic linkers, can achieve selective adsorption owing to their high chemical and structural tunability. Their selectivity and flexibility make MOFs attractive for gas sensing, as realized in novel low-power, low-footprint, on-chip devices such as the chemical-sensitive field-effect transistor, previously demonstrated by our group. In this...