Exploring Piezoelectric and Piezophototronic Properties of Nanostructured LN-ZnSnS3 for Photo Responsive Vibrational Energy Harvesting

Abstract

Piezoelectric energy harvesters have for some time become an advanced choice for self-powered electronics. While oxide based piezoelectric nanomaterials are well studied for their quality mechanical energy harvesting potential, the recent interest to develop multifunctional nanomaterials for harvesting simultaneous ferroelectric/ piezoelectric and light energy for photodetectors, photovoltaics and piezophototronics have compelled to search for newer semiconducting dipolar materials. In this direction,LiNbO3 type-ZnSnS3 (LN-ZTS) is predicted to have low optical band gap energy, and possess considerably expanded hexagonal R3c lattice with high ferroelectricity. Though have been stabilised in thin film form, LN-ZTS has not been reported to be synthesized exclusively. In this article, we report a one-step synthesis of R3c hexagonal LN-type ZnSnS3 (ZTS) nanoflakes and show that it can be a highly desirable candidate for light responsive mechanical energy harvesting via impressive piezophototronic effect. A piezoelectric coefficient (d33) of ~ 19 pm/V was measured from piezoresponse force microscopy and a considerable zero bias photoconduction current was observed, which was utilized to harvest an output power ~0.13 µW/cm² from induced light intensity of 100 mW/cm² under a mechanical impact of 17 N, 3 Hz. These findings establish not yet reported ternary sulphide piezoelectric nanocrystals as potential candidates for designing piezophototronic devices by coupling optical functionalities and piezoelectric responses.