The Electronic Impact of Light-induced Degradation in CsPbBr3 Perovskite Nanocrystals at Gold Interfaces
Fredrik Johansson a b, Azmat Ali b, Herve Crugel b, Erika Giangrisostomi c, Ruslan Ovsyanniikov c, Mathieu Silly d, Lenart Dudy d, Ute Cappel a, Emmanuel Lhuillier b, Nadine Witkowski b
a Condensed Matter Physics of Energy Materials, Division of X-ray Photon Science, Department of Physics and Astronomy, Uppsala University
b Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, France, Place Jussieu, 4, Paris, France
c Helmholtz Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz, 1, Berlin, Germany
d Synchrotron SOLEIL, L’Orme des Merisiers Saint-Aubin, Gif-sur-Yvette, France
Oral, Fredrik Johansson, presentation 075
Publication date: 6th February 2024

The understanding of interfacial properties in perovskite devices under irradiation is crucial for their engineering, for instance in devices where electrodes are in direct contact with the perovskite such as certain scintillator designs.

We show how the electronic structure of the interface between CsPbBr3 perovskite nanocrystals (PNCs) and Au is affected by irradiation of X-rays, near infrared (NIR) and ultraviolet (UV) light. The effect of X-ray and light exposure could be differentiated by employing low-dose X-ray photoelectron spectroscopy (XPS) available at the Bessy II synchrotron in Berlin. A combination of a pulsed, low flux X-ray source, and a high transmission electron analyzer allow recording of XPS spectra without damaging even radiation sensitive samples. A coupled laser provides both NIR and UV light making it possible to isolate the effects of the light exposure. 

Apart from the common degradation product of metallic lead (Pb0), a new intermediate component (Pbint) was identified in the Pb 4f XPS spectra after exposure to high intensity X-rays or UV light. The Pbint component is determined to be metallic Pb on-top of the Au substrate formed from underpotential deposition (UPD, a surface-limited redox process) of Pb induced from damage of the perovskite allowing for migration of Pb2+. This has implications on all devices where the perosvkite could come in contact with gold, and potentially also for other metals used as electrode materials. 

© FUNDACIO DE LA COMUNITAT VALENCIANA SCITO
We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info