Tin dioxide nano-wire device for sensing kinetics of acetone and ethanol towards diabetes monitoring

摘要

We demonstrate how to establish reliable contacts to SnO2 nano-wires by growing these nano-wire on-chip on gold contacts deposited on alumina. The sensor device is used to sense the concentrations of acetone and ethanol in air and their reaction kinetics. Acetone molecules have higher adsorption and desorption rates on SnO2 nanowires than ethanol molecules which leads to a lower critical acetone concentration at which the SnO2 sensor saturates than is the case for ethanol. These differences suggest a new way of introducing selectivity to the notoriously non-selective SnO2 and other oxide-based nano-scale sensors.