Ultrasensitive room-temperature geranyl acetone detection based on Fe@WO3−x nanoparticles in cooked rice flavor analysis

Abstract

In the assessment of food quality, geranyl acetone plays a crucial role as a volatile organic compound (VOC) biomarker for diverse agricultural products, while the ultralow concentration detection meeting application requirements has been barely studied. Herein, an iron (Fe)-doped WO3−x gas sensor was employed for greatly sensitive, selective, and scalable geranyl acetone detection. The results proved that precisely-regulated oxygen vacancy (OV) and sophisticatedly-active electron transition of Fe-doped WO3−x nanoparticles were fulfilled by modifying the doping amount of Fe3+, leading to the prominently enhanced sensitivity (23.47 at 6 ppm), low limit of detection (LOD) (237 ppb), optimal selectivity, and outstanding long-term stability. Furthermore, the enhancing mechanism of gas sensing performance was substantiated through density functional theory (DFT) calculation, while the practical application for the evaluation of spoiled cooked rice was conducted as well. This study demonstrates a reliable method for detecting a VOC biomarker in cooked rice, which can ensure food security and improve palatability of cooked rice.