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Kinetic pathway for interfacial electron transfer from a semiconductor to a molecule

Abstract

Molecular approaches to solar-energy conversion require a kinetic optimization of light-induced electron-transfer reactions. At molecular–semiconductor interfaces, this optimization has previously been accomplished through control of the distance between the semiconductor donor and the molecular acceptor and/or the free energy that accompanies electron transfer. Here we show that a kinetic pathway for electron transfer from a semiconductor to a molecular acceptor also exists and provides an alternative method for the control of interfacial kinetics. The pathway was identified by the rational design of molecules in which the distance and the driving force were held near parity and only the geometric torsion about a xylyl- or phenylthiophene bridge was varied. Electronic coupling through the phenyl bridge was a factor of ten greater than that through the xylyl bridge. Comparative studies revealed a significant bridge dependence for electron transfer that could not be rationalized by a change in distance or driving force. Instead, the data indicate an interfacial electron-transfer pathway that utilizes the aromatic bridge orbitals.

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Figure 1: The strategy utilized to demonstrate an electron-transfer pathway from TiO2 to a molecule.
Figure 2: The interfacial density of states for 1p/TiO2, 1x/TiO2, 2p/TiO2 and 2x/TiO2.
Figure 3: Spectroscopic and kinetic evidence of a pathway for interfacial electron transfer from TiO2 to the remote TPA•+.

References

  1. Closs, G. L. & Miller, J. R. Intramolecular long-distance electron transfer in organic molecules. Science 240, 440–447 (1988).

    Article  CAS  Google Scholar 

  2. Davis, W. B., Svec, W. A., Ratner, M. A. & Wasielewski, M. R. Molecular-wire behaviour in p-phenylenevinylene oligomers. Nature 396, 60–63 (1998).

    Article  CAS  Google Scholar 

  3. Lambert, C., Noll, G. & Schelter, J. Bridge-mediated hopping or superexchange electron-transfer processes in bis(triarylamine) systems. Nature Mater. 1, 69–73 (2002).

    Article  CAS  Google Scholar 

  4. Vura-Weis, J. et al. Crossover from single-step tunneling to multistep hopping for molecular triplet energy transfer. Science 328, 1547–1550 (2010).

    Article  CAS  PubMed  Google Scholar 

  5. Ardo, S. & Meyer, G. J. Photodriven heterogeneous charge transfer with transition-metal compounds anchored to TiO2 semiconductor surfaces. Chem. Soc. Rev. 38, 115–164 (2009).

    Article  CAS  PubMed  Google Scholar 

  6. Abrahamsson, M. et al. Decreased interfacial charge recombination rate constants with N3-type sensitizers. J. Phys. Chem. Lett. 1, 1725–1728 (2010).

    Article  CAS  Google Scholar 

  7. Asbury, J. B., Hao, E. C., Wang, Y. Q. & Lian, T. Q. Bridge length-dependent ultrafast electron transfer from Re polypyridyl complexes to nanocrystalline TiO2 thin films studied by femtosecond infrared spectroscopy. J. Phys. Chem. B 104, 11957–11964 (2000).

    Article  CAS  Google Scholar 

  8. Haque, S. A. et al. Supermolecular control of charge transfer in dye-sensitized nanocrystalline TiO2 films: towards a quantitative structure–function relationship. Angew. Chem. Int. Ed. 44, 5740–5744 (2005).

    Article  CAS  Google Scholar 

  9. Cameron, P. J. & Peter, L. M. Characterization of titanium dioxide blocking layers in dye-sensitized nanocrystalline solar cells. J. Phys. Chem. B 107, 14394–14400 (2003).

    Article  CAS  Google Scholar 

  10. Palomares, E., Clifford, J. N., Haque, S. A., Lutz, T. & Durrant, J. R. Control of charge recombination dynamics in dye sensitized solar cells by the use of conformally deposited metal oxide blocking layers. J. Am. Chem. Soc. 125, 475–482 (2003).

    Article  CAS  PubMed  Google Scholar 

  11. Taube, H. & Myers, H. Evidence for a bridged activated complex for electron transfer reactions. J. Am. Chem. Soc. 76, 2103–2111 (1954).

    Article  CAS  Google Scholar 

  12. Beratan, D. N., Betts, J. N. & Onuchic, J. N. Protein electron transfer rates set by the bridging secondary and tertiary structure. Science 252, 1285–1288 (1991).

    Article  CAS  PubMed  Google Scholar 

  13. Beratan, D. N., Onuchic, J. N., Winkler, J. R. & Gray, H. B. Electron-tunneling pathways in proteins. Science 258, 1740–1741 (1992).

    Article  CAS  PubMed  Google Scholar 

  14. Wenger, O. S. Photoinduced electron and energy transfer in phenylene oligomers. Chem. Soc. Rev. 40, 3538–3550 (2011).

    Article  CAS  PubMed  Google Scholar 

  15. Hopfield, J. J. Electron transfer between biological molecules by thermally activated tunneling. Proc. Natl Acad. Sci. USA 71, 3640–3644 (1974).

    Article  CAS  PubMed  Google Scholar 

  16. Moser, C., Page, C., Farid, R. & Dutton, P. L. Biological electron transfer. J. Bioenerg. Biomembr. 27, 263–274 (1995).

    Article  CAS  PubMed  Google Scholar 

  17. Haque, S. A., Tachibana, Y., Klug, D. R. & Durrant, J. R. Charge recombination kinetics in dye-sensitized nanocrystalline titanium dioxide films under externally applied bias. J. Phys. Chem. B 102, 1745–1749 (1998).

    Article  CAS  Google Scholar 

  18. Brigham, E. C. & Meyer, G. J. Ostwald isolation to determine the reaction order for TiO2(e)|S+ → TiO2|S charge recombination at sensitized TiO2 interfaces. J. Phys. Chem. C 118, 7886–7893 (2014).

    Article  CAS  Google Scholar 

  19. Clifford, J. N. et al. Molecular control of recombination dynamics in dye-sensitized nanocrystalline TiO2 films: free energy vs distance dependence. J. Am. Chem. Soc. 126, 5225–5233 (2004).

    Article  CAS  PubMed  Google Scholar 

  20. Hasselmann, G. M. & Meyer, G. J. Diffusion-limited interfacial electron transfer with large apparent driving forces. J. Phys. Chem. B 103, 7671–7675 (1999).

    Article  CAS  Google Scholar 

  21. Maggio, E. & Troisi, A. Theory of the charge recombination reaction at the semiconductor–adsorbate interface in the presence of defects. J. Phys. Chem. C 117, 24196–24205 (2013).

    Article  CAS  Google Scholar 

  22. Hu, K. et al. Intramolecular and lateral intermolecular hole transfer at the sensitized TiO2 interface. J. Am. Chem. Soc. 136, 1034–1046 (2014).

    Article  CAS  PubMed  Google Scholar 

  23. Kuciauskas, D., Freund, M. S., Gray, H. B., Winkler, J. R. & Lewis, N. S. Electron transfer dynamics in nanocrystalline titanium dioxide solar cells sensitized with ruthenium or osmium polypyridyl complexes. J. Phys. Chem. B 105, 392–403 (2001).

    Article  CAS  Google Scholar 

  24. Ashford, D. L. et al. Photoinduced electron transfer in a chromophore–catalyst assembly anchored to TiO2 . J. Am. Chem. Soc. 134, 19189–19198 (2012).

    Article  CAS  PubMed  Google Scholar 

  25. Barzykin, A. V. & Tachiya, M. Mechanism of molecular control of recombination dynamics in dye-sensitized nanocrystalline semiconductor films. J. Phys. Chem. B 108, 8385–8389 (2004).

    Article  CAS  Google Scholar 

  26. Hanson, K. et al. Structure–property relationships in phosphonate-derivatized, RuII polypyridyl dyes on metal oxide surfaces in an aqueous environment. J. Phys. Chem. C 116, 14837–14847 (2012).

    Article  CAS  Google Scholar 

  27. Nelson, J. Continuous-time random-walk model of electron transport in nanocrystalline TiO2 electrodes. Phys. Rev. B 59, 15374–15380 (1999).

    Article  CAS  Google Scholar 

  28. Huang, Z. J. et al. Dye-controlled interfacial electron transfer for high-current indium tin oxide photocathodes. Angew. Chem. Int. Ed. 54, 6857–6861 (2015).

    Article  CAS  Google Scholar 

  29. Hu, K., Robson, K. C. D., Johansson, P. G., Berlinguette, C. P. & Meyer, G. J. Intramolecular hole transfer at sensitized TiO2 interfaces. J. Am. Chem. Soc. 134, 8352–8355 (2012).

    Article  CAS  PubMed  Google Scholar 

  30. Ardo, S., Sun, Y., Staniszewski, A., Castellano, F. N. & Meyer, G. J. Stark effects after excited-state interfacial electron transfer at sensitized TiO2 nanocrystallites. J. Am. Chem. Soc. 132, 6696–6709 (2010).

    Article  CAS  PubMed  Google Scholar 

  31. Brunschwig, B. S., Creutz, C. & Sutin, N. Optical transitions of symmetrical mixed-valence systems in the Class II–III transition regime. Chem. Soc. Rev. 31, 168–184 (2002).

    Article  CAS  PubMed  Google Scholar 

  32. Chen, P. Y. & Meyer, T. J. Medium effects on charge transfer in metal complexes. Chem. Rev. 98, 1439–1477 (1998).

    Article  CAS  PubMed  Google Scholar 

  33. Williams, G. & Watts, D. C. Non-symmetrical dielectric relaxation behaviour arising from a simple empirical decay function. Trans. Faraday Soc. 66, 80–85 (1970).

    Article  CAS  Google Scholar 

  34. Lindsey, C. P. & Patterson, G. D. Detailed comparison of the Williams–Watts and Cole–Davidson functions. J. Chem. Phys. 73, 3348–3357 (1980).

    Article  CAS  Google Scholar 

  35. Knutson, J. R., Walbridge, D. G. & Brand, L. Decay-associated fluorescence spectra and the heterogeneous emission of alcohol-dehydrogenase. Biochemistry 21, 4671–4679 (1982).

    Article  CAS  PubMed  Google Scholar 

  36. Robson, K. C. D., Koivisto, B. D., Gordon, T. J., Baumgartner, T. & Berlinguette, C. P. Triphenylamine-modified ruthenium(II) terpyridine complexes: enhancement of light absorption by conjugated bridging motifs. Inorg. Chem. 49, 5335–5337 (2010).

    Article  CAS  PubMed  Google Scholar 

  37. Chen, C.-Y. et al. Multifunctionalized ruthenium-based supersensitizers for highly efficient dye-sensitized solar cells. Angew. Chem. Int. Ed. 47, 7342–7345 (2008).

    Article  CAS  Google Scholar 

  38. Song, H. E. et al. Linker dependence of energy and hole transfer in neutral and oxidized multiporphyrin arrays. J. Phys. Chem. B 113, 16483–16493 (2009).

    Article  CAS  PubMed  Google Scholar 

  39. Chen, P. Y., Curry, M. & Meyer, T. J. Effects of conformational change in the acceptor on intramolecular electron transfer. Inorg. Chem. 28, 2271–2280 (1989).

    Article  CAS  Google Scholar 

  40. Hanss, D., Walther, M. E. & Wenger, O. S. Importance of covalence, conformational effects and tunneling-barrier heights for long-range electron transfer: insights from dyads with oligo-p-phenylene, oligo-p-xylene and oligo-p-dimethoxybenzene bridges. Coord. Chem. Rev. 254, 2584–2592 (2010).

    Article  CAS  Google Scholar 

  41. Laine, P. P., Bedioui, F., Loiseau, F., Chiorboli, C. & Campagna, S. Conformationally gated photoinduced processes within photosensitizer–acceptor dyads based on osmium(II) complexes with triarylpyridinio-functionalized terpyridyl ligands: insights from experimental study. J. Am. Chem. Soc. 128, 7510–7521 (2006).

    Article  CAS  PubMed  Google Scholar 

  42. Meylemans, H. A., Lei, C. F. & Damrauer, N. H. Ligand structure, conformational dynamics, and excited-state electron delocalization for control of photoinduced electron transfer rates in synthetic donor–bridge–acceptor systems. Inorg. Chem. 47, 4060–4076 (2008).

    Article  CAS  PubMed  Google Scholar 

  43. Sun, D. L., Rosokha, S. V., Lindeman, S. V. & Kochi, J. K. Intervalence (charge-resonance) transitions in organic mixed-valence systems. Through-space versus through-bond electron transfer between bridged aromatic (redox) centers. J. Am. Chem. Soc. 125, 15950–15963 (2003).

    Article  CAS  PubMed  Google Scholar 

  44. Shen, J.-J. & Zhong, Y.-W. Long-range ruthenium–amine electronic communication through the para-oligophenylene wire. Sci. Rep. 5, 13835 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  45. Argazzi, R., Bignozzi, C. A., Heimer, T. A., Castellano, F. N. & Meyer, G. J. Enhanced spectral sensitivity from ruthenium(II) polypyridyl based photovoltaic devices. Inorg. Chem. 33, 5741–5749 (1994).

    Article  CAS  Google Scholar 

  46. Pavlishchuk, V. V. & Addison, A. W. Conversion constants for redox potentials measured versus different reference electrodes in acetonitrile solutions at 25 °C. Inorg. Chim. Acta 298, 97–102 (2000).

    Article  CAS  Google Scholar 

  47. Johansson, P. G. et al. Long-wavelength sensitization of TiO2 by ruthenium diimine compounds with low-lying π* orbitals. Langmuir 27, 14522–14531 (2011).

    Article  CAS  PubMed  Google Scholar 

  48. Frisch, M. J. et al. Gaussian 09 (Gaussian, Inc., 2009).

  49. Robson, K. C. D. et al. Systematic modulation of a bichromic cyclometalated ruthenium(II) scaffold bearing a redox-active triphenylamine constituent. Inorg. Chem. 50, 6019–6028 (2011).

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

The University of North Carolina (UNC) authors gratefully acknowledge support by a grant from the Division of Chemical Sciences, Office of Basic Energy Sciences, Office of Energy Research, US Department of Energy (DE-SC0013461). The University of British Columbia authors are grateful to the Canadian Natural Science and Engineering Research Council, Canadian Foundation for Innovation, Canadian Institute for Advanced Research and Canada Research Chairs for support. The authors thank M. Gish and the Papanikolas group at UNC for the ultrafast measurements.

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G.J.M., C.P.B. and K.H. proposed the ideas, A.D.B. and P.A.S. synthesized the compounds, K.H. and R.N.S. performed the electrochemical and photophysical experiments and K.H., R.N.S. and E.J.P. analysed the data. E.J.P. performed the Mulliken–Hush analysis, F.G.L.P. constructed Fig. 1 and G.J.M. wrote the manuscript with input from all the authors. G.J.M. and C.P.B. supervised the project.

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Correspondence to Gerald J. Meyer or Curtis P. Berlinguette.

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Hu, K., Blair, A., Piechota, E. et al. Kinetic pathway for interfacial electron transfer from a semiconductor to a molecule. Nature Chem 8, 853–859 (2016). https://doi.org/10.1038/nchem.2549

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