Photovoltaic properties of hybrid c-Si/ZnO nanorod solar cells

Abstract

We report on the hydrothermal synthesis of high quality polycrystalline zinc oxide nanorod arrays grown on indium tin oxide substrates. We observe a clear effect of the nucleation and growth rates on the morphology and orientation of the nanorod arrays, with a predominance of the polycrystalline hexagonal wurtzite structure and preferential c-axis orientation. In addition, we studied the effect of the growth orientation and morphology of the ZnO nanorod arrays on light absorption. The changes in crystalline structure and defects are attributed to kinetic effects driven by temperature. Finally, using PC1D software, we describe the charge transport and photovoltaic properties of simulated hybrid c-Si solar cells by considering the lengths of the ZnO NRs and the reflectance values. The 1.1 μm average length of the ZnO NRs is found to be the optimum value for achieving the highest power conversion efficiency of ∼15.48%. The simulation study for the vertically arranged ZnO NRs anti-reflection layers shows that the low-temperature grown ZnO NRs on the c-Si solar cells is promising for the realization of low-cost and efficient hybrid solar cells.