Characterization of Enzymatically Synthesized Titania Thin Films Using Positron Annihilation Spectroscopy Reveals Low-Cost Approach for Organic/Inorganic Photovoltaic Cells

Journal Article (2020)
Author(s)

E.F. van Amelrooy (Student TU Delft)

H. Schut (TU Delft - RST/Neutron and Positron Methods in Materials)

W. Egger (University of the Federal Armed Forces Munich)

Marcel Dickmann (Technische Universität München)

Christoph Hugenschmidt (Technische Universität München)

L. Mallée (TU Delft - BT/Biocatalysis)

Ulf Hanefeld (TU Delft - BT/Biocatalysis)

D.G.G. McMillan (TU Delft - BT/Biocatalysis)

SWH Eijt (TU Delft - RST/Fundamental Aspects of Materials and Energy)

Research Group
RST/Fundamental Aspects of Materials and Energy
Copyright
© 2020 E.F. van Amelrooy, H. Schut, Werner Egger, Marcel Dickmann, Christoph Hugenschmidt, L. Mallée, U. Hanefeld, D.G.G. McMillan, S.W.H. Eijt
DOI related publication
https://doi.org/10.1002/adsu.202000003
More Info
expand_more
Publication Year
2020
Language
English
Copyright
© 2020 E.F. van Amelrooy, H. Schut, Werner Egger, Marcel Dickmann, Christoph Hugenschmidt, L. Mallée, U. Hanefeld, D.G.G. McMillan, S.W.H. Eijt
Research Group
RST/Fundamental Aspects of Materials and Energy
Issue number
6
Volume number
4
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

A new method is developed to produce mesoporous titania thin films at room temperature using the enzyme papain in a dip-coating procedure, providing low-cost titania films in a sustainable manner. Quartz crystal microbalance, positron annihilation Doppler broadening and lifetime spectroscopy, scanning electron microscopy, and X-ray diffraction are used to determine the deposition and structural properties of the films. As-deposited films have low densities ρ ≈ 0.6 g cm−3, contain small micropores and proteins, and exhibit corrugated surfaces. Annealing at temperatures of 300 °C or higher leads to the destruction and evaporation of most of the organic material, resulting in a thickness decrease of 50–60%, more pure titania films with increased density, an increase in micropore size and a decrease in the concentration and size of atomic-scale vacancies. Up to 50 layers could be stacked, allowing easy control over the total layer thickness. Based on these titania films, first test devices consisting of natural dye-sensitized solar cells are produced, that show photovoltaic activity and indicate possibilities for low-cost, accessible, organic production of solar cells. Given the wide range of other applications for titania, this new method is a promising candidate for improving the fabrication of those products with respect to cost, sustainability, and production speed.