Erica Chin, Xiaopeng Li, and Zhiyong Gu. Chemical Engineering, University of Massachusetts Lowell, One University Ave, Lowell, MA 01854
Metal oxide thin films have been widely used as sensors for various types of gases and chemical agents. Nanowires (including metal oxide nanowires) have been shown to have higher sensitivity as sensors; the incorporation of dopants into a metal oxide is an efficient way in which the selectivity of sensors can be significantly increased. In this research, we propose to use metal oxide nanowires with different dopants for explosive detection. Electrodeposition in nanoporous templates is used to synthesize multi-segmented tin oxide (SnO2) nanowires. Dopants are incorporated into the sensor segment during electrodeposition. SEM and TEM along with EDAX are used to characterize the nanowires fabricated. The nanowires are dispersed onto a Si/SiO2 surface and then assembled between two electrodes using microfabrication techniques, including photolithography and metal deposition, to form a sensor device. Nanowire sensors with different dopants are exposed to explosives for electrical measurements, and both sensitivity and selectivity are studied in order to improve and optimize the sensor performance.