Flexible amino acid-based energy harvesting for structural health monitoring of water pipes

Biomolecular piezoelectric materials offer an inexpensive, non-toxic, and renewable alternative to current commercial piezoelectrics, which rely on toxic heavy elements. Currently, there is a lack of testing for real-world applications of these eco-friendly crystals. Here, we validate an amino acid-based sensor capable of real-time detection of pipe leakage, a global challenge for sustainable water access. The polycrystalline device demonstrates data-driven decision making in identifying degraded pipelines, exploiting the relationship between leak-induced vibration and piezoelectric voltage. The device has piezoelectric strain and voltage constants of 0.9 pC/N and 60 mV m/N. Peak voltage of ∼2 V is recorded in the low-dielectric film at high flow rates and large leak size. The glycine crystal sensors demonstrate much higher sensitivity than PVDF polymer patches. The sensors can operate over a range of test leak sizes, with the energy content of the worst leak state being >10 times that of a healthy pipe.