Nanogenerator-based bidirectional pressure sensor array and its demonstration in underwater invasive species detection

Assessment of spawning-phase dynamics is an essential prerequisite to successful control of invasive sea lampreys in Great Lakes areas, which cause catastrophic damages in both commercial fishery and ecological systems. However, current assessment strategies may pose challenges for lake-wide abundance estimation and non-target anadromous species preservation. Here, we demonstrate an efficacious species-specific non-destructive sensing system based on porous ferroelectret nanogenerator for in-situ monitoring of lamprey spawning migration using their unique suction behavior. Simulations show that the porous structure enables a redistribution of surface charges under bidirectional deformations, which allows the detection of both positive and negative pressures. The quasi-piezoelectric effect is further validated by quantitative analysis in a wide pressure range of −50 to 60 kPa, providing detailed insights into transduction working principles. For reliable lamprey detection, a 4 × 4-pixel sensor array is developed and integrated with a complementary metal-oxide-semiconductor (CMOS) based signal processing array thus constituting a sensing panel capable of recording oral suction patterns in an underwater environment.