Breath Level Acetone Discrimination Through Temperature Modulation of a Hierarchical ZnO Gas Sensor

A hierarchical ZnO nanostructure gas sensor was fabricated to evaluate the concentration of acetone in exhaled human breath. Such information can be used for the diagnosis of diabetes since acetone levels in exhaled breath in excess of 1.8ppm are typically associated with diabetes sufferers. When exposed to acetone, the fabricated sensor exhibits a unique U-shaped response curve as a function of temperature. It was discovered that its acetone sensing behavior changes from oxidizing to reducing as the temperature increases. The sensor's characteristic response was shown to be associated to the carbonyl group present in the acetone molecule. The fabricated hierarchical ZnO nanostructure sensor is able to detect acetone concentration levels as low as 1ppm even at room temperature, making it suitable for noninvasive diabetes diagnosis.