Pyroelectrically-Charged Flexible Piezoelectret Sensors: Route Towards Sustainable Functional Electronics

In this manuscript, a pyroelectrically-charged flexible polydimethylsiloxane (PDMS) piezoelectret force sensor is reported. The proposed pyroelectric charge trapping approach supports low power operation, small footprint, uniform charge distribution, and chip-scale integration for recharging capability. Various flexible porous PDMS membranes (150 mm in diameter, ~100 µm-thick) are fabricated using a water-in-PDMS emulsion technique for controlled pore size (0.6 – 142 µm) and their piezoelectric coefficients are measured to be 70–170 pC/N, representing increases of 100% to 450% after charging. Finally, the charged membranes were used as a pressure sensor array, allowing the recording of a human step.