TY - JOUR
T1 - Characterization of Enzymatically Synthesized Titania Thin Films Using Positron Annihilation Spectroscopy Reveals Low-Cost Approach for Organic/Inorganic Photovoltaic Cells
AU - van Amelrooij, Edward F.
AU - Schut, Henk
AU - Egger, Werner
AU - Dickmann, Marcel
AU - Hugenschmidt, Christoph
AU - Mallée, Lloyd
AU - Hanefeld, Ulf
AU - McMillan, Duncan G.G.
AU - Eijt, Stephan W.H.
PY - 2020
Y1 - 2020
N2 - 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.
AB - 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.
KW - biomineralization
KW - enzymes
KW - photovoltaics
KW - positron annihilation
KW - titania
UR - http://www.scopus.com/inward/record.url?scp=85080984268&partnerID=8YFLogxK
U2 - 10.1002/adsu.202000003
DO - 10.1002/adsu.202000003
M3 - Article
AN - SCOPUS:85080984268
SN - 2366-7486
VL - 4
JO - Advanced Sustainable Systems
JF - Advanced Sustainable Systems
IS - 6
M1 - 2000003
ER -