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Title: BODIPY Chemisorbed on SnO2 and TiO2 Surfaces for Photoelectrochemical Applications
Advancement toward dye-sensitized photoelectrochemical cells to produce solar fuels by solar-driven water splitting requires a photosensitizer that is firmly attached to the semiconducting photoelectrodes. Covalent binding enhances the efficiency of electron injection from the photoexcited dye into the metal oxide. Optimization of charge transfer, efficient electron injection, and minimal electron-hole recombination are mandatory for achieving high efficiencies. Here, a BODIPY-based dye exploiting an innovative surface-anchoring mode via boron is compared with a similar dye bound by a traditional carboxylic acid anchoring group. Through terahertz and transient absorption spectroscopic studies, along with GFN-xTB calculations, we find that, when compared to the traditional carboxylic acid anchoring group, electron injection of boron-bound BODIPY is faster into both TiO2 and SnO2. Although the surface coverage is low compared with carboxylic acids, the binding stability is improved over a wide range of pH. Subsequent photoelectrochemical studies using a sacrificial electron donor showed this combined dye and anchoring group maintained photocurrent with good stability over long-time irradiation. This recently discovered binding mode of BODIPY shows excellent electron injection and good stability over time, making it promising for future investigations.  more » « less
Award ID(s):
2305138
NSF-PAR ID:
10504176
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Applied Materials & Interfaces
Volume:
16
Issue:
12
ISSN:
1944-8244
Page Range / eLocation ID:
14841 to 14851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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