Proceedings of International Conference Asia-Pacific Hybrid and Organic Photovoltaics 2018 (AP-HOPV18)
DOI: https://doi.org/10.29363/nanoge.ap-hopv.2018.044
Publication date: 27th October 2017
Experiments suggests that electrical heterogeneity in both the perovskite active layer, as well as the perovskite/electrode interface, can affect carrier diffusion and non-radiative recombination processes within perovskite solar cells. In this talk we will describe both confocal and conductive atomic force microscopy (cAFM) to explore the role of heterogeneities and grain boundaries on lateral carrier transport, and will demonstrate varying degrees of grain boundary opacity to carrier transport depending on the structure. In this talk, we will also discuss both ligand exchange and cation exchange experiments in the context of tailoring the properties of halide perovskite thin films. We show that with controlled passivation of the perovskite surfaces we are able to obtain carrier lifetimes and PL intensities in solution-processed thin films that rival those in the best single crystals, achieving over 90% PL internal quantum efficiency and quasi-Fermi level splittings that exceed 96% of the Shockley-Queisser limit under illumination. Combining these results with experiments demonstrating contact-induced losses in many common perovskite architectures, we then explore new contact materials and their potential for increased efficiency.