Low recombination rates and improving charge transfer as decisive conditions for high current densities and fill factors in ZnS complex systems

Abstract

The growth of ZnS photoelectrodes on ZnO particles identified as ZnO/ZnS(ZC + TAA) by the microwave-assisted hydrothermal method showed excellent photovoltaic parameters of J_SC = 1.2 mA cm⁻² and FF = 0.66, even compared to ZnS(ZC + TAA) used as a reference sample with J_SC = 0.15 mA cm⁻² and FF = 0.52. A careful analysis indicates that the better charge transfer and the higher resistance to recombination present in the ZnO/ZnS(ZC + TAA) samples were the origin of the best photovoltaic behavior. These assertions are supported by a set of samples synthesized from different precursors resulting in different crystal structures, which can be directly associated with current densities and fill factors. All aspects about synthesis and optical/electronic parameters associated with structural features will be available in this article.