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

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

van Amelrooy, E.F. (Student TU Delft)
Schut, H. (TU Delft RST/Neutron and Positron Methods in Materials)
Egger, Werner (University of the Federal Armed Forces Munich)
Dickmann, Marcel (Technische Universität München)
Hugenschmidt, Christoph (Technische Universität München)
Mallée, L. (TU Delft BT/Biocatalysis)
Hanefeld, U. (TU Delft BT/Biocatalysis)
McMillan, D.G.G. (TU Delft BT/Biocatalysis)
Eijt, S.W.H. (TU Delft RST/Fundamental Aspects of Materials and Energy)

2020

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.

biomineralization
enzymes
photovoltaics
positron annihilation
titania

http://resolver.tudelft.nl/uuid:55289778-5fda-4718-bb9d-d64ecc6c444f

https://doi.org/10.1002/adsu.202000003

2366-7486

Advanced Sustainable Systems, 4 (6)

Institutional Repository

journal article

© 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