Nanostructured zinc stannate perovskite films synthesized via molten salt modified-solvothermal method for enhanced piezoelectric properties

Abstract

Three dimensional (3D) piezoelectric zinc stannate (ZnSnO₃) nanoweb arrays are synthesized using a molten salt modified solvothermal method and deposited in PDMS films for electrochemical analysis of its piezoelectric response. This work is a preliminary assessment of comparative piezoelectric efficacy influenced by changes in synthesis, effecting dimension and particle size. Advantages of hydrothermal, molten salt, and solvothermal synthesis methods were leveraged to facilitate several chemical and surface engineering techniques to enhance piezoelectric properties by increasing the surface area of zinc stannate nanoparticles. The combination of these treatments reduce the size of zinc stannate to approximately ∼40nm-80nm weblike networks. Scanning electron microscopy (SEM) and X-Ray Diffraction (XRD) analysis reveal a mesoporous protonated tristannate (H₂Sn₃O₇) nanoweb template with connecting wirelike strands having diameters ranging from 12-27nm across and pores up to 50nm in diameter. Subsequent solvothermal treatment produces the perovskite nanoweb in a mixed solvent solution of critical dielectric conditions found to be 80% ethanol and 20% water for maximum Zn²⁺ deposition. ZnSnO₃ nanowebs (NW) were deposited in PDMS thin films and used as a piezoelectric nanogenerator (PENG) to characterize its electrochemical properties. Comparative voltage analysis of PDMS films made with weight percentages of (0%, 1%, 5%, 10%, 15% and 20%) zinc stannate sub-microcubes and nanowebs morphologies were done using an oscilloscope. These tests reveal an increased voltage output for the zinc stannate nanoweb morphology. The combination of these synthesis methods forming 3D zinc stannate nanoweb arrays could have far-reaching implications in producing other metal oxides when approaching the design of perovskite nanomaterials and piezoelectric energy harvesting systems in the coming decade.