Elucidating ultra-fast charge transfer in CsPbBr, the effect of nanocrystals and transition metal dichalcogenides
Perovskite nanocrystals have shown great promise as light harvesting material for solar cells. Preliminary studies show that charge transfer occurs in at different time scales in CsPbBr3, from nanoseconds to a few femtoseconds. The charge transfer is also different between nanocrystals and bulk material and is shortened when in contact with a transition metal dichalcogenide. We propose to use core-hole clock spectroscopy to study the ultra-fast charge in bulk and nanocrystals of CsPbBr3 and try to quicken the charge transfer in the nanocrystals by introducing a transition metal dichalcogenide.
Status: Ongoing
Date of proposal: 24/08/2022
Start date: 20/09/2022
End Date: 26/09/2022
Used Instruments: HZB_XPS/HAXPES
Experimental Technique: Core-hole clock spectroscopy. Resonant Auger spectroscopy. X-Ray Photoelectron Spectroscopy (XPS). Hard X-Ray Photoelectron Spectroscopy (HAXPES).
Experiment Description: The project aimed to study ultra-fast charge transfer in CsPbBr3 perovskite materials, specifically focusing on the effect of nanocrystals and transition metal dichalcogenides (like MoS2). The research utilized core-hole clock spectroscopy to analyze ultra-fast charge transfer in both bulk and nanocrystals of CsPbBr3.
Type Samples: CsPbBr3 nanocrystals on TiO2. CsPbBr3 nanocrystals on MoS2. CsPbBr3 bulk thin film on TiO2.
Sample Description: Samples prepared with CsPbBr3 perovskite in different configurations, including with nanocrystals on TiO2 and MoS2 substrates, and a bulk thin film on TiO2.
Experiment Data Type: X-Ray Absorption Spectra (XAS) at Cs L2 and Pb M3 edges. Resonant Auger data.
Characterization Technics: Resonant Auger and core-hole clock spectroscopy. XPS and HAXPES for chemical analysis.
Characterization Data Type: Analysis of charge transfer dynamics in CsPbBr3. Study of the electronic structure and interactions in the material.
Analyzed Data: Comparative analysis of charge transfer in different configurations of CsPbBr3. Understanding of ultra-fast charge transfer mechanisms in perovskite nanocrystals and bulk materials.
Main Targets Project: Elucidating ultra-fast charge transfer in CsPbBr3 perovskite. Investigating the effects of nanocrystals and transition metal dichalcogenides on charge transfer.
Main Achievements Findings: Successful measurement of resonant Auger regions of Pb and Cs, including the first measurement of Cs resonant Auger in the hard/tender x-ray range. Found that the charge transfer is different between nanocrystals and bulk material and is shortened when in contact with MoS2. Observed differences in XAS and resonant Auger spectra between different samples, suggesting variations in charge transfer and electronic structure.
Review 16
How would you describe your experience with the VIPERLAB opportunity? How did the experience/visit at HZB_XPS/HAXPESmeet your expectations?
It is a very nice opportunity to allow for experiments at state-of-the-art experimental facilities and networking within the community.The overall experience of VIPERLAB is positive, from an easy application process to smooth running experiments at HZB with good and friendly user support.
Did you face any difficulties during your visit or application process?
Does this VIPERLAB experience at HZB-EMIL bring you closer to your research objectives? How?
Yes, it does. It allowed me to successfully perform an experiment essential to my post-doctoral project on the electron charge transfer dynamics in perovskite nanocrystal interfaces.
What other VIPERLAB activities have you participated in, or would you like to participate in?
This is the only activity I have participated in so far. I would like to participate in future project within HZB-EMIL.
Do you intend or already did publish/present your collected results in a paper or conference?
The analysis of the data is ongoing and is planned for publication in a journal.