Tribo-piezoelectric synergistic BaTiO₃/PDMS micropyramidal structure for high-performance energy harvester and high-sensitivity tactile sensing

Triboelectric nanogenerators (TENGs) and piezoelectric nanogenerators (PENGs) represent some of the most promising strategies for converting mechanical deformation and friction into electrical energy. This energy can be used to power electronic devices, such as wearables, and detect mechanical stimuli. Here, we have demonstrated the synergistic integration of piezoelectric and triboelectric effects by incorporating barium titanate (BaTiO3) nanoparticles into a pyramidal polydimethylsiloxane (PDMS) elastomer. This integration aims to enhance the performance of both pressure sensor devices and electrical energy harvesters. The pressure sensitivity of our proposed tribo-piezoelectric device reaches as high as 3.71 V center dot kPa(-1) for pressure sensing within the range of 0.1-100 kPa, the output voltage increasing to similar to 370 V at 100 kPa. Our theoretical simulation of electrical power density at this specific pressure reveals that the mechanical deformation of the PDMS elastomer, combined with the polarization of BaTiO3 nanoparticles, synergistically generate tribo-piezoelectric charge on the surface. Therefore, our synergistic combination of triboelectric and piezoelectric effects opens a promising avenue for effectively converting mechanical action into electrical signals. This enables highly efficient energy scavenging and the development of high-sensitivity pressure sensors.