Perovskite Nanomaterials: Transport Studies and Devices

• Autores: Alvaro Javier Magdaleno de Benito
• Directores de la Tesis: Ferry Prins (dir. tes.)
• Lectura: En la Universidad Autónoma de Madrid ( España ) en 2023
• Idioma: inglés
• Número de páginas: 128
• Enlaces
  • Tesis en acceso abierto en: Biblos-e Archivo
• Resumen

  • Metal-halide perovskites have been object of intense research during the last two decades because of their remarkable optoelectronic properties. However, the short stability of 3D perovskites when exposed to ambient conditions is a limiting factor to their applicability. 2D perovskites have emerged as a more robust alternative. They are composed by an alternating stack of organic spacer layers with the perovskite crystalline lattice. This layered nanostructure makes the energy transport to be governed by excitons (electron-hole bound states), in opposite to the 3D perovskites, where there is free carrier transport. The last one has been extensively studied in 3D perovskites. However, exciton transport studies in 2D perovskites are scarcer. It is important to understand its fundamentals to boost the efciency of 2D perovskite-based devices. Transient photoluminescence microscopy (TPLM) visualizes the spatial and temporal dynamics of an energy carrier population generated within the material under examination. From these measurements we extract complete information of the exciton dynamics and elaborate models to understand the microscopic origin of such dynamics.

    This thesis aims to contribute on the uncovering of exciton transport properties in 2D perovskites by using TPLM. Firstly, we visualize an efcient interlayer exciton transport within these materials. This contrast with the interlayer free carriers transport, which is almost negligible, given the insulating nature of the organic spacers. Secondly, we visualize the role of exciton difusion in the emission of manganese-doped 2D perovskites. Mn-doped perovskites are promising for light emitting applications due to the high improvement in photoluminescence quantum yield and ambient stability of some perovskite materials trough Mn-doping. Herein we visualize that the difusion of the excitons populates the Mn dopants with the subsequent Mn-emission. Highlighting the importance of the difusion to transport the energy towards the Mn-states. Thirdly, we show a new set-up to boost the efciency of TPLM by concentrating a higher amount of the photoluminescence spot within the scanned region. We use a set of cylindrical lenses for this purpose and enhance the collected intensity up to x6. Finally, we make use of the bandgap tunability of perovskites trough halide mixing to develop easy-to-make perovskite-on-paper photodetectors with variable spectral response. Paper substrates are promising for biodegradable and much cheaper electronic devices