TY - JOUR
T1 - Insights into the Mechanism of a Covalently Linked Organic Dye–Cobaloxime Catalyst System for Dye-Sensitized Solar Fuel Devices
AU - Pati, Palas Baran
AU - Zhang, Lei
AU - Philippe, Bertrand
AU - Fernández-Terán, Ricardo
AU - Ahmadi, Sareh
AU - Tian, Lei
AU - Rensmo, Håkan
AU - Hammarström, Leif
AU - Tian, Haining
N1 - Funding Information:
This work was financially supported by the Swedish Energy Agency, the Knut and Alice Wallenberg Foundation, the ?forsk Foundation (nr.14-452), the joint ?Climate Change? program between the Swedish Research Council (VR) and the National Research Foundation of Korea (NRF), Olle Engkvist Builder Foundation and G?ran Gustafsson Foundation. We would also like to greatly thank Prof. Sascha Ott (UU) and Prof. Gerrit Boschloo (UU) for their kind lab support, Mr. Jens F?hlinger (UU) and Dr. Starla Glover (UU) for their helpful discussion and Mr. Leif H?ggman (UU) for providing ZrO2 films. L.Z. and L.T. thank the China Scholarship Council (CSC) for the scholarship support. The authors also acknowledge Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX) for providing the computational resources under the project SNIC-2015-6-104 and HZB for the allocation of synchrotron radiation beam time.
PY - 2017/6/9
Y1 - 2017/6/9
N2 - A covalently linked organic dye–cobaloxime catalyst system based on mesoporous NiO is synthesized by a facile click reaction for mechanistic studies and application in a dye-sensitized solar fuel device. The system is systematically investigated by photoelectrochemical measurements, density functional theory, time-resolved fluorescence, transient absorption spectroscopy, and photoelectron spectroscopy. The results show that irradiation of the dye–catalyst on NiO leads to ultrafast hole injection into NiO from the excited dye, followed by a fast electron transfer process to reduce the catalyst. Moreover, the dye adopts different structures with different excited state energies, and excitation energy transfer occurs between neighboring molecules on the semiconductor surface. The photoelectrochemical experiments also show hydrogen production by this system. The axial chloride ligands of the catalyst are released during photocatalysis to create the active sites for proton reduction. A working mechanism of the dye–catalyst system on the photocathode is proposed on the basis of this study.
AB - A covalently linked organic dye–cobaloxime catalyst system based on mesoporous NiO is synthesized by a facile click reaction for mechanistic studies and application in a dye-sensitized solar fuel device. The system is systematically investigated by photoelectrochemical measurements, density functional theory, time-resolved fluorescence, transient absorption spectroscopy, and photoelectron spectroscopy. The results show that irradiation of the dye–catalyst on NiO leads to ultrafast hole injection into NiO from the excited dye, followed by a fast electron transfer process to reduce the catalyst. Moreover, the dye adopts different structures with different excited state energies, and excitation energy transfer occurs between neighboring molecules on the semiconductor surface. The photoelectrochemical experiments also show hydrogen production by this system. The axial chloride ligands of the catalyst are released during photocatalysis to create the active sites for proton reduction. A working mechanism of the dye–catalyst system on the photocathode is proposed on the basis of this study.
KW - click chemistry
KW - dye-sensitized solar cells
KW - hydrogen
KW - photocatalysis
KW - reaction mechanisms
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U2 - 10.1002/cssc.201700285
DO - 10.1002/cssc.201700285
M3 - Article
C2 - 28338295
AN - SCOPUS:85018293171
VL - 10
SP - 2480
EP - 2495
JO - ChemSusChem
JF - ChemSusChem
SN - 1864-5631
IS - 11
ER -