Professor Martin Vacha has returned from a one month stay in Prague supported by the WRH Faculty Research Abroad Program. This is a report on the activities and results of his stay.

During a talk at the Institute of Physics of Charles University

 

Awardee	Martin Vacha, Professor, School of Materials and Chemical Technology
Destination Institution	Charles University
City and Country	Prague, Czech Republic
Host Researcher	Jan Valenta, Professor
Travel Period	2024/2/27 – 2024/3/31 (34 Days)
Project Title	Study of nanoscale photophysical properties of perovskite films and solar cell materials by photoluminescence microscopy and spectroscopy

 

Recently, there has been rapid progress in improvement of non-silicon solar cell materials, such as mixed halide perovskites, but the research on the fundamental physical properties that underlie the improved performance has been lacking behind. The study on spectroscopic and photophysical properties of silicon and semiconductor quantum dots has a long tradition at the Charles University in Prague, and the accumulated knowledge is beneficial also for the recent research on the perovskite materials. In addition, there is another center of semiconductor research at the Institute of Physics of the Czech Academy of Sciences in Prague, and the synergy between these places helps to advance the progress in the field.

I visited the group of Professor Jan Valenta at the Charles University for one month to carry out experiments on correlated measurements of nanoscale photophysical properties and absolute photoluminescence quantum efficiency on triple-cation perovskite films deposited on different substrates to clarify the effect of the interface between the perovskite films and the hole-transporting or electron-transporting layers.

Apart from the experiments, I gave an invited talk at the Department of Chemical Physics on March 14 on the topic of ‘Nanoscale spectroscopy of perovskites’. In addition, I initiated and co-organized a mini-symposium on ‘Advanced preparation and characterization of perovskites’ which took place at the Institute of Physics on March 19. The symposium included seven talks and was attended by scientists from the Institute of Physics, from the Charles University and from the Catholic University in Leuven, Belgium.

The collaborative research and, in particular, the scientific interactions enabled by the organization of the mini-symposium revealed many points of common interest between the participants. Different groups specialize in methods and techniques that are to large extent complimentary and their use in research collaborations will bring qualitative progress in advanced characterization of the photophysical properties of perovskites. As a concrete output, a manuscript including the results obtained during the stay is currently under preparation.

Related links:
– World Research Hub (WRH) Program
– Vacha Lab