Proceedings of International Conference on Perovskite Thin Film Photovoltaics and Perovskite Photonics and Optoelectronics (NIPHO20)
DOI: https://doi.org/10.29363/nanoge.nipho.2020.047
Publication date: 25th November 2019
In this work, we introduce a synthesis of ligand-free ABX3 perovskite nanocrystals (nc-ABX3) based on the use of porous metal oxide (MOx) thin films with a controlled nanopore size as a template. The liquid precursors infiltrate these structures helped by spin coater method, then a smooth thermal treatment leads to nc-ABX3s in the voids of the porous network of TiO2. We demonstrated that the reaction volume imposed by the nanoporous scaffold leads to the strict control of the nanocrystal size, which allows us to observe well-defined quantum confinement effects on the photo-emission. In addition, our methodology provides fine spectral tuning of the luminescence with maximum precision by only changing the concentration of the precursors. Nc-ABX3 /MOx film presents high photoluminescence quantum yield (>60% in many cases), high optical quality and mechanical stability. It also permits subsequent elastomer infiltration to achieve a self-standing flexible film, which keeps the photo-emission efficiency of the nc-AMX3 unaltered and prevents the degradation from the external environment (water, humidity). Applications as adaptable color-converting layers for light-emitting devices are envisaged and demonstrated. Finally, we demonstrate that the embeded nanocrystals support charge transport in a solar cell device configuration achieving 8% photoconversion when we use SiO2 nanoparticles as porous scaffold.