Interconnected ZnO branches as an effective electron transfer layer in perovskite solar cells

Abstract In this paper, ZnO nanobranches are successfully synthesised by a simple solution-based process and served as electron transport layer in perovskite solar cells (PSC). The structure and chemical composition of the synthesized ZnO branches and nanowires were characterised by using a scanning electron microscopy equipped with an energy dispersive spectroscopy. Also the X-ray diffraction measurements and photoluminescence emission measurements were performed to gain understanding of the crystal phase and quality of the samples. The proposed ZnO nanobranches outperforms conventional vertically aligned ZnO nanowire by almost 85% due to the enhanced charge collection and reduction in structural defects from the second annealing process.