Research team
Unravelling chirality of perovskites at atomic and nanometer scale via advanced low-dose electron microscopy for next-generation optoelectronics.
Abstract
Metal halide perovskites (MHPs) are highly promising semiconductors for novel optoelectronic devices. A timely goal is to extend the use of MHPs to chiroptoelectronic applications, such as circularly polarized light photodetectors. Due to the flexibility of arranging the organic and inorganic building blocks in perovskites, it recently became possible to synthesize chiral perovskites with a non-centrosymmetric crystal structure. In my project I will focus on MHP nanocrystals (NCs) containing chiral cations and MHP NCs assembled in a three-dimensional chiral morphology. For both systems, the chirality transfer mechanisms are not yet understood. Therefore, the aim of my project is to exploit advanced transmission electron microscopy (TEM), including 4D scanning TEM, electron tomography and electron diffraction to quantify the helicity of self-assembled structures and the occurring distortions of the inorganic framework in MHPs with chiral cations. Due to the high beam sensitivity of MHPs and organic cations the development of novel low-dose techniques will be crucial. The insights on chiral MHPs, obtained from this project will pave the way to design novel chiroptical devices.Researcher(s)
- Promoter: Bals Sara
- Fellow: Schrenker Nadine
Research team(s)
Project type(s)
- Research Project
Low dose in situ electron microscopy study on metal halide perovskites: Unravelling the role of defects and degradation mechanisms under bias, oxygen and moisture.
Abstract
Metal halide perovskites (MHP) are promising semiconductors for the next generation of optoelectronic applications because of their excellent performance and low-cost processability. Unfortunately, applications are hampered by the lack of stability when MHPs are exposed to relevant conditions. To overcome this limitation, precise knowledge of the structure-property relationship in MHPs is required. Therefore, this project aims to develop novel and advanced transmission electron microscopy (TEM) techniques for in situ experiments, during which MHPS will be exposed to environmental conditions. Hereby, the development of low dose TEM techniques is crucial because of the high electron beam-sensitivity of MHPs. These techniques will be combined with in situ experiments under heat, gaseous environment, and high bias. Based on the outcome of my experiments, I will be able to provide a better understanding of promising stabilization methods such as interfacial clamping. I will hereby reveal the influence of interfacial defects and grain boundary types in textured MHP thin films. Moreover, the local results obtained by TEM will yield novel insights on degradation mechanisms under high bias, oxygen or moisture. In this manner, my project will provide the necessary input to trigger novel strategies for long-term stability of MHPs.Researcher(s)
- Promoter: Bals Sara
- Fellow: Schrenker Nadine
Research team(s)
Project type(s)
- Research Project