Physics of degRadation in Organic, nanoCrystal, and hybrid solar cEllS (PROCES)

• Applicant: Professorin Dr. Yana Vaynzof
• Subject Area: Experimental Condensed Matter Physics ; Synthesis and Properties of Functional Materials
• Term: from 2017 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 391347809

Facing the rising energy usage worldwide, we urgently need to increase the proportion of electricity generated from clean and renewable energy sources. Organic, colloidal nanocrystal quantum dots (QDs), and hybrid organic-inorganic perovskites are highly promising solution-processable material candidates for "third-generation" solar cells. Their unique material characteristics can lead to flexible, light-weight, lowcost and high-performance solar cells and enable non-conventional solar cell products. While theefficiencies are being improved constantly by intensive research, the Achilles heel of these devices seems to be their environmental instability. So far only limited research has been done to study the fundamental causes and mechanisms leading to the environmental instability in devices based on organic, nanocrystal and hybrid perovskite materials. Developing a clear understanding of the physicochemical processes ofdegradation would aid the integration of these devices into industrial applications, guiding both material and device engineering to improve device lifetimes.Therefore, in this "PROCES" project we aim to (1) identify the fundamental causes of degradation of organic, inorganic nanocrystal and hybrid organic-inorganic thin films; (2) understand the physical origin of degradation, i.e. the formation of degradation products; (3) correlate the changes in device characteristics to the causes identified; and (4) develop strategies to improve material and device stability.It can be anticipated that through this study we will gain fundamental understanding of how different choices of materials (organic, nanocrystal, or hybrid components), their synthetic and surface chemistry, and different device architectures, impact on the device degradation mechanisms. Understanding these aspects will not only lead to organic, quantum dot and hybrid solar cells with improved device lifetimes, but also offer material and device design guidelines for further optimization of future third-generation photovoltaics.This 3-year ANR-DFG project will be carried out by a tight collaboration between two research teams from Heidelberg University (Germany) and the LPEM (Laboratoire de Physique et d'Etude des Matériaux, a research unit of CNRS/ESPCI-ParisTech/Université Pierre et Marie Curie). The project will build on the strength and expertise of these two teams to allow for a multidisciplinary investigation. The results of this collaborative approach will boost the research capability of each team surpassing its current level and allowing an ideal platform to tackle the complex and multi-domain challenges to maximize the environmental stability in organic, inorganic nanocrystal and hybrid organic-inorganic material systems.

• DFG Programme: Research Grants
• International Connection: France
• Cooperation Partner: Zhuoying Chen, Ph.D.