Self-powered wireless rapid oil quality sensing system based on triboelectric-discharge effect

The rapid assessment of the free fatty acid (FFA) content in edible oils plays a pivotal role in ensuring food quality and safety. However, current methods suffer from disadvantages such as bulky systems, labor-intensive procedure, and high costs, restricting their applicability. Herein, we developed a self-powered, wireless, rapid oil quality sensing system (SWOS) based on the triboelectric-discharge (TD) effect, which enables the real-time rapid monitoring of FFAs in edible oils. A sliding freestanding-triboelectric-layer mode triboelectric nanogenerator (SFT-TENG) was designed to convert mechanical energy into high-voltage electrical output, which triggers gas discharge and generates wireless signals containing information about the edible oils’ quality. Based on this strategy, we have successfully established a strong correlation between the FFA content in edible oils and the decay time of wireless signals. In addition, the device was demonstrated to offer in-situ quantification of the FFA content in a rapid and self-powered manner. This achievement presents a portable tool for the rapid detection of the FFA content in edible oils which may contribute to food safety monitoring and quality assurance.