A Strategy to Enhance Humidity Robustness of p?Type CuO Sensors for Breath Acetone Quantification

Low-cost metal oxide sensors are highly attractive for emerging applications such as breath analysis. Particularly promising p-type that can operate at low temperatures, a key requirement compact and low-power devices. To date, however, these lack sufficient sensitivity, selectivity, humidity robustness to fulfil stringent requirements faced in real applications. Herein, flame-made sensor (operated 150 °C) consists of CeO2-decorated CuO nanoparticles is introduced, determined by X-ray diffraction photoelectron spectroscopy Most remarkably, this features excellent 10–90% relative humidity. This attributed the presence CeO2 nanoclusters, which may act scavenging OH? allow readsorption oxygen onto surface. demonstrate its immediate impact, investigated detection acetone, biomarker fat burning. It detects acetone with high sensitivity (i.e., 50 ppb) selectivity (>9.8) toward inorganic interferants NH3, H2, CO). importantly, CeO2–CuO accurately quantifies concentrations exhaled 16 volunteers (bias precision 90 457 ppb). As result, it robust volatiles