ISBN 9783843943154

978-3-8439-4315-4, Reihe Anorganische Chemie

Alexander Möllmann
Nanostructured Metal Oxide Thin Films as Electron Transport Material for Inorganic-Organic Hybrid Perovskite Solar Cells

174 Seiten, Dissertation Universität Köln (2019), Softcover, A5

Zusammenfassung / Abstract

In this work, inorganic-organic hybrid perovskite solar cells were developed and the suitability of binary and ternary metal oxides as electron transport materials in perovskite solar cells was evaluated. Firstly, a standard process for the fabrication of multilayer perovskite solar cell was established, to evaluate the stability and efficiency of above-mentioned metal oxides as ETMs in perovskite solar cells. Through systematic variation of electron and hole transfer materials, perovskite absorber layers and contact material, PSCs in different configurations were developed. For this purpose, various thin film techniques such as spin coating, spray pyrolysis, atomic layer deposition and plasma enhanced chemical vapor deposition, were used to deposit functional layers in desired architecture. A range of semiconductor metal oxide, such as TiO2, Ta2O5, CeO2, U3O8 and LaNbO4 were tested in this work, because of their optical and electronic properties, wide band gaps and n-type semiconductor behaviour. Compared to prototype ETM TiO2, other compositions, explored in this work, have not been reported in literature as electron transport material in perovskite solar cells and could potentially improve the device efficiency and stability, due to a better band alignment and the lack of photocatalytic activity. The fundamental electron transfer dynamics of the used metal oxides in PSCs were investigated by steady-state and transient photoluminescence spectroscopy. The type of band alignment was determined via ultraviolet photoelectron spectroscopy and Tauc plots. Besides the replacement of the ETM, a superhydrophobic encapsulant, (SiOxCyHz), was deposited by plasma-enhanced chemical vapour deposition, which delayed the degradation of the perovskite absorber as successfully demonstrated by long-term stability studies.