Research Article Cite This: ACS Sustainable Chem. Eng. XXXX, XXX, XXX−XXX
pubs.acs.org/journal/ascecg
Insight into Interface Engineering at TiO2/Dye through Molecularly Functionalized Caf1 Biopolymer Seckin Akin,†,‡ Yakup Ulusu,§,∥ Helen Waller,∥ Jeremy H. Lakey,∥ and Savas Sonmezoglu*,†,‡ †
Department of Metallurgical & Materials Engineering, ‡Nanotechnology R&D Laboratory, §Department of Bioengineering, and Karamanoglu Mehmetbey University, 70100 Karaman, Turkey ∥ Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom S Supporting Information *
ABSTRACT: The fast charge recombination kinetics and poor sensitizing ability in dye-sensitized solar cells (DSSCs) result in a significant electron loss and performance degradation. However, the retarding of electron recombination and/or increasing light-harvesting efficiency (LHE) via employing an appropriate interface modifier in DSSCs has rarely been investigated. Here, we first report a molecularly engineered Caf1 protein (both in monomeric and polymeric forms) to modify the surface states by effectively shielding the unfavorable reactions and improve the light absorption properties by introducing alternative anchoring facilities. Using the novel Caf1 biopolymer with high thermal stability (even at 90 °C), we achieved an unprecedented efficiency of 8.31% under standard illumination test conditions and maintain the output performance even under prolonged irradiation. Time-resolved fluorescence spectroscopy measurement reveals an improved electron transfer rate (kET = 0.26 to 0.98 × 108 s−1), whereas the Voc decay rate is lower (70% decay in 90 s) for Caf1-P@TiO2 based cells than that of bare ones (∼85% decay in
