Synergistic Gas Sensing and Superhydrophobic Composites Enabled Real-Time Detection of Milk Spoilage
Year: 2025
Type: article
Abstract: Milk spoilage detection remains a critical challenge in food safety and waste reduction, demanding advanced real-time monitoring solutions. Metal oxide gas sensors offer potential for volatile compound detection, but limited by room-temperature sensitivity and liquid-rich environments. Here, we present a SnO2/Montmorillonite (MMT)@Wax composite integrating enhanced gas-sensing capabilities with superhydrophobicity. The sensing mechanism exploits two synergistic effects: (i) Polarization enhancement through cation-electron interactions (Al3+/K+/ /Mg2+) in MMT lamellae, which facilitates charge transfer by releasing immobilized electrons during analyte adsorption, (ii) heterojunction formation between SnO2 and MMT through Mg2+-Al3+ substitution-induced localized negative charge regions. The hierarchical wax coating confers exceptional superhydrophobicity without obvious compromising gas permeability, enabling reliable operation in high-liquid environments. Real-time monitoring trials demonstrated accurate spoilage detection at the fourth day at 30 °C, also verified with pH change and gas chromatography analysis. And a continuous monitoring demonstrated the spoilage occurred initially at 3800-4300 min. This work would provide a scalable, cost-effective, and field-deployable solution for real-time quality monitoring of liquid foods.
Source: ACS Sensors
Authors: Ning Tian, Meng Wang, Qixue Song, Lin Liu, Zhaofeng Wu
Institution: Xinjiang University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
Awards: G4535172457, G6681945811
OpenAlex ID: W4416925701