Room Temperature-Based ZnO/WSe2 VOC (Hexanal, 1-Octen-3-ol, 1-Pentanol) Sensor for Red Meat Degradation

Abstract

Food spoilage leads to the release of volatile organic compounds (VOCs), which can serve as early indicators of degradation. This work demonstrates the development of a room-temperature ZnO/WSe₂ sensor for real-time monitoring of VOCs (hexanal, 1-octen-3-ol, 1-pentanol, etc.) emitted during food degradation, specifically from red meat. The fabricated ZnO/WSe₂ hexanal sensor exhibited an excellent response of ∼ 22.02% at lower concentration of hexanal ranging from 100 ppb at room temperature. Also, a set of experiments using binary and ternary mixtures was conducted to investigate the sensor’s behavior when multiple volatiles were present in the surroundings. The sensor exhibits high selectivity toward hexanal, high stability (up to 30 days), repeatability (100, 200, 400 ppb concentration of hexanal), with a rapid response time (389 s) and recovery time (161 s). The charge transfer mechanism is explained by the energy band diagram extracted by ultraviolet photoelectron spectroscopy. Finally, in order to verify the significance of VOCs from food degradation, real raw meat species was analyzed by the fabricated ZnO/WSe₂ sensor at room temperature and the possible uses of this sensor are in food quality monitoring.