Integrated Smart Gas Tracking Device with Artificially Tailored Selectivity for Real-Time Monitoring Food Freshness

Abstract

The real-time monitoring of food freshness in refrigerators is of significant importance in detecting potential food spoiling and preventing serious health issues. One method that is commonly reported and has received substantial attention is the discrimination of food freshness via the tracking of volatile molecules. Nevertheless, the ambient environment of low temperature (normally below 4 °C) and high humidity (90% R.H.), as well as poor selectivity in sensing gas species remain the challenge. In this research, an integrated smart gas-tracking device is designed and fabricated. By applying pump voltage on the yttria-stabilized zirconia (YSZ) membrane, the oxygen concentration in the testing chamber can be manually tailored. Due to the working principle of the sensor following the mixed potential behavior, distinct differences in sensitivity and selectivity are observed for the sensor that operated at different oxygen concentrations. Typically, the sensor gives satisfactory selectivity to H2S, NH3, and C2H5OH at the oxygen concentrations of 10%, 30%, and 40%, respectively. In addition, an acceptable response/recovery rate (within 24 s) is also confirmed. Finally, a refrigerator prototype that includes the smart gas sensor is built, and satisfactory performance in discriminating food freshness status of fresh or semi-fresh is verified for the proposed refrigerator prototype. In conclusion, these aforementioned promising results suggest that the proposed integrated smart gas sensor could be a potential candidate for alarming food spoilage.

CuO/TiO2/MXene-Based Sensor and SMS-TENG Array Integrated Inspection Robots for Self-Powered Ethanol Detection and Alarm at Room Temperature

“…14 Therefore, it is needed to develop an effective energy harvesting method to reduce energy consumption and achieve economical and energy-saving storage monitoring, and it is also necessary to be more intelligent in the monitoring of the storage process. 15 Gas detection sensor is a class of devices used to monitor the concentration of specific gases in the environment, and a large number of studies have been conducted to apply them to food freshness detection, 16 wearable sensing, 17,18 and human health monitoring. 19 In particular, metal oxide semiconductors have been widely studied and used for gas sensing applications.…”

“…Gas detection sensor is a class of devices used to monitor the concentration of specific gases in the environment, and a large number of studies have been conducted to apply them to food freshness detection, wearable sensing, , and human health monitoring . In particular, metal oxide semiconductors have been widely studied and used for gas sensing applications. − Cheng et al proposed a fast RT ZnO-based volatile organic compound (VOC) sensor based on self-powered triboelectric plasma in situ regulation technology for detecting acetone .…”