Abstract
A newly synthesized nanomaterial known as KxW7O22 (KxWO) exhibits a stable room-temperature ferroelectric property. This unique ferroelectric property has revealed that KxWO is a promising material for application in a breath sensor, which can be used for patients to monitor their daily health condition and diagnose disease at every early stage with low cost, convenience, and non-invasion. In this study, we successfully synthesized nano-structured KxWO through a low cost but high yield hydrothermal method. The sensing response of KxWO to acetone is examined based on a chemiresistive effect. For the first time, we systematically studied how material structures and the component, potassium (K), can affect KxWO-based sensing performance. The results indicate that the low temperature ferroelectric property of KxWO causes an excellent response to acetone, which is the biomarker for diabetes. The lowest detection limit can be down to 0.1 ppm and the KxWO-based sensor can operate at room temperature. In addition, the Kx component KxWO and its crystal structure also play an important role in improving its sensing performance. Our results provide advanced research in (1) exploring the study of KxWO material properties by tailoring the concentration of the potassium in KxWO and introducing the surfactant Pluronic L-121 in the growing process, and (2) optimizing KxWO sensing performance by controlling its material properties.