Materials Science and Engineering and Applied Physics Graduate Seminar

Abstract

We explore the development, growth and understanding of new semiconductor materials for solar cells, including photoactive light-absorbers and transparent electrodes with either n- or p-type conductivity.

First, we will show how understanding of growth from the atomic to the macroscale leads to enhanced electron mobility in transparent conducting oxides (TCO), and with this achieve optimum broadband transparent n-type semiconductors with conductivity close to a metal.^1,2

Second, we will discuss how material design and controlled synthesis have enabled us to experimentally demonstrate transparent p-type conductive materials, which have been a major and longstanding challenge in optoelectronic materials. Exploring beyond oxides and moving to halide and chalco-halide systems, semiconductors with a disperse valence band can be fabricated. Disperse valence band semiconductors present improved hole mobility, contrary to the case of oxide semiconductors.

Finally, we will present recent developments in a versatile vacuum- and laser-based deposition method for controlling the fabrication of hybrid organic-inorganic materials, using the example of hybrid metal halide perovskites^3,4. We will demonstrate how this method leads to the stabilization of photoactive phases and the creation of high-quality thin films, which can then be integrated as absorbers into solar cell devices.

In summary, the presentation will highlight how controlled synthesis, material design and integration of new materials into proof-of-concept devices make a significant contribution to the emerging generation of efficient and sustainable solar cell devices.

[1] https://doi.org/10.1002/admt.202000856

[2] https://doi.org/10.1038/s43246-022-00260-4        

[3] https://doi.org/10.1021/acs.chemmater.1c02054

[4] https://doi.org/10.1002/adfm.202300588

Bio

Monica Morales-Masis is Professor at the University of Twente (UT), The Netherlands which she joined in 2018. From 2013 to 2018 she was team leader of the transparent conductive oxide (TCO) group at the Photovoltaics and Thin-Film Electronics Laboratory (PVLab) of the Ecole Polytechnique Federale de Lausanne (EPFL), Switzerland. She obtained her Ph.D. in Physics from Leiden University in 2012. Currently, her group at UT focuses on the development and understanding of novel thin film materials with functional optical and electrical properties for optoelectronic devices, including solar cells. Her current research program is financed by the NWO StartUp grant and the European Research Council (ERC) Starting Grant and Proof-of Concept grants.