Effect of the Dielectric and Mechanical Properties of the Polymer Matrix on ZnO-Nanowire-Based Composite Nanogenerators Performance

The effect of Young's Modulus and dielectric permittivity of the polymer matrix in vertically integrated nanogenerators (VING) on their output performance is studied by combining Finite Element Method (FEM) and analytical modeling. To conduct this study, an elementary cell is considered, based on one ZnO nanowire surrounded by the polymer matrix. We demonstrate that the polymer matrix should have the lowest Young's Modulus and permittivity as possible, in order to maximize the output voltage and power. Four different materials, which have already been proposed in literature for such composite VING, are then compared: Parylene C, PMMA, Al2O3 and PDMS. Simulation results show that PDMS, who has the lowest values of both Young's Modulus and permittivity, gives the highest output performance. Finally, the sensitivity to another design parameter-the surface density of nanowires-is calculated, and this study shows that choosing a polymer material with the lowest Young's Modulus and permittivity is more powerful to improve the VING performance.