Boosting the optoelectronic performance of Perovskite Nanocrystals for LED applications

Organic-inorganic lead halide perovskites are semiconductor materials with outstanding optical properties, turning them into excellent candidates for devices employed in light-harvesting and emission. Perovskite crystals possess a large absorption coefficient and long charge carrier diffusion lengths, which is highly desirable for solar cell applications. For light-emitting diodes (LEDs), impressive progress in the photoluminescence quantum efficiency has been made, owing to the wide range of color tunability and high color purity of this material. However, perovskite crystals lose their emission efficiency and stability due to the presence of unwanted crystal surface defects. Recently, low-dimensional perovskites have gained considerable attention due to their remarkable stability and narrow fluorescence emission spectra, making them attractive for LED applications. However, optimal luminescence efficiency is not yet achieved. In this PhD proposal, the focus is set on developing perovskite NCs with improved optoelectronic performance and stability, mainly through surface engineering via the use of ligands and/or the formation of low-dimensional structures. Next, thin film formation will be optimized and LEDs will be fabricated. During this process, an in-depth micro- and spectroscopic study will be conducted. Lastly, the project scope will be extended toward Pb-free perovskites.