Nano Research

, Volume 9, Issue 11, pp 3515–3527 | Cite as

Unraveling the mark of surface defects on a spinterface: The nitronyl nitroxide/TiO2(110) interface

  • Reza Kakavandi
  • Arrigo Calzolari
  • Yulia B. Borozdina
  • Prince Ravat
  • Thomas Chassé
  • Martin Baumgarten
  • M. Benedetta Casu
Research Article

Abstract

Metal-free organic radicals are fascinating materials owing to their unique properties. Having a stable magnetic moment coupled to light elements makes these materials central to develop a large variety of applications. We investigated the magnetic spinterface coupling between the surface of a single rutile TiO2(110) crystal and a pyrene-based nitronyl nitroxide radical, using a combination of thickness-dependent X-ray photoelectron spectroscopy and ab initio calculations. The radicals were physisorbed, and their magnetic character was preserved on the (almost) ideal surface. The situation changed completely when the molecules interacted with a surface defect site upon adsorption. In this case, the reactivity of the defect site led to the quenching of the molecular magnetic moment. Our work elucidates the crucial role played by the surface defects and demonstrates that photoemission spectroscopy combined with density functional theory calculations can be used to shed light on the mechanisms governing complex interfaces, such as those between magnetic molecules and metal oxides.

Keywords

organic spinterface photoemission spectroscopy density functional theory calculations 

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Unraveling the mark of surface defects on a spinterface: The nitronyl nitroxide/TiO2(110) interface

References

  1. [1]
    Getzlaff, M. Fundamentals of Magnetism; Springer-Verlag: Berlin, Heidelberg, 2008.Google Scholar
  2. [2]
    Gatteschi, D.; Sessoli, R.; Villain, J. Molecular Nanomagnets; Oxford University Press: New York, 2006.CrossRefGoogle Scholar
  3. [3]
    Nobelprize.org. The Nobel Prize in Physics 2007 [Online]. http://www.nobelprize.org/nobel_prizes/physics/laureates/2 007/(accessed Jul 14, 2016).Google Scholar
  4. [4]
    Wolf, S. A.; Awschalom, D. D.; Buhrman, R. A.; Daughton, J. M.; von Molnár, S.; Roukes, M. L.; Chtchelkanova, A. Y.; Treger, D. M. Spintronics: A spin-based electronics vision for the future. Science 2001, 294, 1488–1495.CrossRefGoogle Scholar
  5. [5]
    Sanvito, S. Molecular spintronics. Chem. Soc. Rev. 2011, 40, 3336–3355.CrossRefGoogle Scholar
  6. [6]
    Miller, J. S. Magnetically ordered molecule-based materials. Chem. Soc. Rev. 2011, 40, 3266–3296.CrossRefGoogle Scholar
  7. [7]
    Epifanov, G. I. Solid State Physics; Mir Publisher: Moscow, 1979.Google Scholar
  8. [8]
    Caneschi, A.; Ferraro, F.; Gatteschi, D.; le Lirzin, A.; Novak, M. A.; Rentschler, E.; Sessoli, R. Ferromagnetic order in the sulfur-containing nitronyl nitroxide radical, 2-(4-thiomethyl)phenyl-4,4,5,5-tetramethylimidazoline-l-ox yl-3-oxide, NIT(SMe)Ph. Adv. Mater. 1995, 7, 476–478.CrossRefGoogle Scholar
  9. [9]
    Tamura, M.; Nakazawa, Y.; Shiomi, D.; Nozawa, K.; Hosokoshi, Y.; Ishikawa, M.; Takahashi, M.; Kinoshita, M. Bulk ferromagnetism in the ß-phase crystal of the p-nitrophenyl nitronyl nitroxide radical. Chem. Phys. Lett. 1991, 186, 401–404.CrossRefGoogle Scholar
  10. [10]
    Zhang, Y.-H.; Kahle, S.; Herden, T.; Stroh, C.; Mayor, M.; Schlickum, U.; Ternes, M.; Wahl, P.; Kern, K. Temperature and magnetic field dependence of a Kondo system in the weak coupling regime. Nat. Commun. 2013, 4, 2110.Google Scholar
  11. [11]
    Liu, J.; Isshiki, H.; Katoh, K.; Morita, T.; Breedlove, B. K.; Yamashita, M.; Komeda, T. First observation of a kondo resonance for a stable neutral pure organic radical, 1,3,5-triphenyl-6-oxoverdazyl, adsorbed on the Au(111) surface. J. Am. Chem. Soc. 2013, 135, 651–658.CrossRefGoogle Scholar
  12. [12]
    Frisenda, R.; Gaudenzi, R.; Franco, C.; Mas-Torrent, M.; Rovira, C.; Veciana, J.; Alcon, I.; Bromley, S. T.; Burzurí, E.; van der Zant, H. S. J. Kondo effect in a neutral and stable all organic radical single molecule break junction. Nano Lett. 2015, 15, 3109–3114.CrossRefGoogle Scholar
  13. [13]
    Hicks, R. G. Stable Radicals: Fundamentals and Applied Aspects of Odd-Electron Compounds; Wiley: Chichester, 2010.Google Scholar
  14. [14]
    Rajca, A.; Shiraishi, K.; Pink, M.; Rajca, S. Triplet (S = 1) ground state aminyl diradical. J. Am. Chem. Soc. 2007, 129, 7232–7233.CrossRefGoogle Scholar
  15. [15]
    Rajca, A.; Olankitwanit, A.; Wang, Y.; Boratynski, P. J.; Pink, M.; Rajca, S. High-spin S = 2 ground state aminyl tetraradicals. J. Am. Chem. Soc. 2013, 135, 18205–18215.CrossRefGoogle Scholar
  16. [16]
    Ullman, E. F.; Call, L.; Osiecki, J. H. Stable free radicals. VIII. New imino, amidino, and carbamoyl nitroxides. J. Org. Chem. 1970, 35, 3623–3631.Google Scholar
  17. [17]
    Caneschi, A.; Gatteschi, D.; Sessoli, R.; Rey, P. Toward molecular magnets: The metal-radical approach. Acc. Chem. Res. 1989, 22, 392–398.CrossRefGoogle Scholar
  18. [18]
    Sun, Z.; Zeng, Z. B.; Wu, J. S. Zethrenes, extended p-quinodimethanes, and periacenes with a singlet biradical ground state. Acc. Chem. Res. 2014, 47, 2582–2591.CrossRefGoogle Scholar
  19. [19]
    Ratera, I.; Veciana, J. Playing with organic radicals as building blocks for functional molecular materials. Chem. Soc. Rev. 2012, 41, 303–349.CrossRefGoogle Scholar
  20. [20]
    Choi, J.; Lee, H.; Kim, K.-J.; Kim, B.; Kim, S. Chemical doping of epitaxial graphene by organic free radicals. J. Phys. Chem. Lett. 2010, 1, 505–509.CrossRefGoogle Scholar
  21. [21]
    Hong, J.; Bekyarova, E.; de Heer, W. A.; Haddon, R. C.; Khizroev, S. Chemically engineered graphene-based 2D organic molecular magnet. ACS Nano 2013, 7, 10011–10022.CrossRefGoogle Scholar
  22. [22]
    Ying, Y. M.; Saini, R. K.; Liang, F.; Sadana, A. K.; Billups, W. E. Functionalization of carbon nanotubes by free radicals. Org. Lett. 2003, 5, 1471–1473.CrossRefGoogle Scholar
  23. [23]
    Mas-Torrent, M.; Crivillers, N.; Mugnaini, V.; Ratera, I.; Rovira, C.; Veciana, J. Organic radicals on surfaces: Towards molecular spintronics. J. Mater. Chem. 2009, 19, 1691–1695.CrossRefGoogle Scholar
  24. [24]
    Grillo, F.; Früchtl, H.; Francis, S. M.; Mugnaini, V.; Oliveros, M.; Veciana, J.; Richardson, N. V. An ordered organic radical adsorbed on a Cu-doped Au(111) surface. Nanoscale 2012, 4, 6718–6721.CrossRefGoogle Scholar
  25. [25]
    Holmberg, R. J.; Hutchings, A.-J.; Habib, F.; Korobkov, I.; Scaiano, J. C.; Murugesu, M. Hybrid nanomaterials: Anchoring magnetic molecules on naked gold nanocrystals. Inorg. Chem. 2013, 52, 14411–14418.CrossRefGoogle Scholar
  26. [26]
    Domingo, N.; Bellido, E.; Ruiz-Molina, D. Advances on structuring, integration and magnetic characterization of molecular nanomagnets on surfaces and devices. Chem. Soc. Rev. 2012, 41, 258–302.CrossRefGoogle Scholar
  27. [27]
    Müllegger, S.; Rashidi, M.; Fattinger, M.; Koch, R. Interactions and self-assembly of stable hydrocarbon radicals on a metal support. J. Phys. Chem. C 2012, 116, 22587–22594.CrossRefGoogle Scholar
  28. [28]
    Lee, J.; Lee, E.; Kim, S.; Bang, G. S.; Shultz, D. A.; Schmidt, R. D.; Forbes, M. D. E.; Lee, H. Nitronyl nitroxide radicals as organic memory elements with both n- and p-type properties. Angew. Chem., Int. Ed. 2011, 50, 4414–4418.CrossRefGoogle Scholar
  29. [29]
    Simão, C.; Mas-Torrent, M.; Crivillers, N.; Lloveras, V.; Artés, J. M.; Gorostiza, P.; Veciana, J.; Rovira, C. A robust molecular platform for non-volatile memory devices with optical and magnetic responses. Nat. Chem. 2011, 3, 359–364.CrossRefGoogle Scholar
  30. [30]
    Tomlinson, E. P.; Hay, M. E.; Boudouris, B. W. Radical polymers and their application to organic electronic devices. Macromolecules 2014, 47, 6145–6158.CrossRefGoogle Scholar
  31. [31]
    Huskinson, B.; Marshak, M. P.; Suh, C.; Er, S.; Gerhardt, M. R.; Galvin, C. J.; Chen, X. D.; Aspuru-Guzik, A.; Gordon, R. G.; Aziz, M. J. A metal-free organic–inorganic aqueous flow battery. Nature 2014, 505, 195–198.CrossRefGoogle Scholar
  32. [32]
    Oyaizu, K.; Nishide, H. Radical polymers for organic electronic devices: A radical departure from conjugated polymers? Adv. Mater. 2009, 21, 2339–2344.CrossRefGoogle Scholar
  33. [33]
    Crivillers, N.; Mas-Torrent, M.; Rovira, C.; Veciana, J. Charge transport through unpaired spin-containing molecules on surfaces. J. Mater. Chem. 2012, 22, 13883–13890.CrossRefGoogle Scholar
  34. [34]
    Sugawara, T.; Komatsu, H.; Suzuki, K. Interplay between magnetism and conductivity derived from spin-polarized donor radicals. Chem. Soc. Rev. 2011, 40, 3105–3118.CrossRefGoogle Scholar
  35. [35]
    Davis, R. M.; Sowers, A. L.; DeGraff, W.; Bernardo, M.; Thetford, A.; Krishna, M. C.; Mitchell, J. B. A novel nitroxide is an effective brain redox imaging contrast agent and in vivo radioprotector. Free Radical Biol. Med. 2011, 51, 780–790.CrossRefGoogle Scholar
  36. [36]
    Sowers, M. A.; McCombs, J. R.; Wang, Y.; Paletta, J. T.; Morton, S. W.; Dreaden, E. C.; Boska, M. D.; Ottaviani, M. F.; Hammond, P. T.; Rajca, A. et al. Redox-responsive branched-bottlebrush polymers for in vivo MRI and fluorescence imaging. Nat. Commun. 2014, 5, 5460.CrossRefGoogle Scholar
  37. [37]
    Rajca, A.; Wang, Y.; Boska, M.; Paletta, J. T.; Olankitwanit, A.; Swanson, M. A.; Mitchell, D. G.; Eaton, S. S.; Eaton, G. R.; Rajca, S. Organic radical contrast agents for magnetic resonance imaging. J. Am. Chem. Soc. 2012, 134, 15724–15727.CrossRefGoogle Scholar
  38. [38]
    Kawanaka, Y.; Shimizu, A.; Shinada, T.; Tanaka, R.; Teki, Y. Using stable radicals to protect pentacene derivatives from photodegradation. Angew. Chem., Int. Ed. 2013, 52, 6643–6647.CrossRefGoogle Scholar
  39. [39]
    Chernick, E. T.; Casillas, R.; Zirzlmeier, J.; Gardner, D. M.; Gruber, M.; Kropp, H.; Meyer, K.; Wasielewski, M. R.; Guldi, D. M.; Tykwinski, R. R. Pentacene appended to a TEMPO stable free radical: The effect of magnetic exchange coupling on photoexcited pentacene. J. Am. Chem. Soc. 2015, 137, 857–863.CrossRefGoogle Scholar
  40. [40]
    Rajca, A. Organic diradicals and polyradicals: From spin coupling to magnetism? Chem. Rev. 1994, 94, 871–893.Google Scholar
  41. [41]
    Blatter, H. M.; Lukaszewski, H. A new stable free radical. Tetrahedron Lett. 1968, 9, 2701–2705.Google Scholar
  42. [42]
    Ciccullo, F.; Gallagher, N. M.; Geladari, O.; Chassé, T.; Rajca, A.; Casu, M. B. A derivative of the blatter radical as a potential metal-free magnet for stable thin films and interfaces. ACS Appl. Mater. Interfaces 2016, 8, 1805–1812.CrossRefGoogle Scholar
  43. [43]
    Lüth, H. Solid Surfaces, Interfaces and Thin Films; Springer: Berlin, Heidelberg, 2010.Google Scholar
  44. [44]
    Sanvito, S. Molecular spintronics: The rise of spinterface science. Nat. Phys. 2010, 6, 562–564.CrossRefGoogle Scholar
  45. [45]
    Barraud, C.; Seneor, P.; Mattana, R.; Fusil, S.; Bouzehouane, K.; Deranlot, C.; Graziosi, P.; Hueso, L.; Bergenti, I.; Dediu, V. et al. Unravelling the role of the interface for spin injection into organic semiconductors. Nat. Phys. 2010, 6, 615–620.CrossRefGoogle Scholar
  46. [46]
    Djeghloul, F.; Ibrahim, F.; Cantoni, M.; Bowen, M.; Joly, L.; Boukari, S.; Ohresser, P.; Bertran, F.; Le Fèvre, P.; Thakur, P. et al. Direct observation of a highly spin-polarized organic spinterface at room temperature. Sci. Rep. 2013, 3, 1272.CrossRefGoogle Scholar
  47. [47]
    Raman, K. V.; Kamerbeek, A. M.; Mukherjee, A.; Atodiresei, N.; Sen, T. K.; Lazic, P.; Caciuc, V.; Michel, R.; Stalke, D.; Mandal, S. K. et al. Interface-engineered templates for molecular spin memory devices. Nature 2013, 493, 509–513.CrossRefGoogle Scholar
  48. [48]
    Javaid, S.; Bowen, M.; Boukari, S.; Joly, L.; Beaufrand, J. B.; Chen, X.; Dappe, Y. J.; Scheurer, F.; Kappler, J. P.; Arabski, J. et al. Impact on interface spin polarization of molecular bonding to metallic surfaces. Phys. Rev. Lett. 2010, 105, 077201.CrossRefGoogle Scholar
  49. [49]
    Galbiati, M.; Tatay, S.; Barraud, C.; Dediu, A. V.; Petroff, F.; Mattana, R.; Seneor, P. Spinterface: Crafting spintronics at the molecular scale. MRS Bull. 2014, 39, 602–607.CrossRefGoogle Scholar
  50. [50]
    Mugnaini, V.; Calzolari, A.; Ovsyannikov, R.; Vollmer, A.; Gonidec, M.; Alcon, I.; Veciana, J.; Pedio, M. Looking inside the perchlorinated trityl radical/metal spinterface through spectroscopy. J. Phys. Chem. Lett. 2015, 6, 2101–2106.CrossRefGoogle Scholar
  51. [51]
    Kakavandi, R.; Savu, S.-A.; Caneschi, A.; Chassé, T.; Casu, M. B. At the interface between organic radicals and TiO2(110) single crystals: Electronic structure and paramagnetic character. Chem. Commun. 2013, 49, 10103–10105.CrossRefGoogle Scholar
  52. [52]
    Savu, S. A.; Biddau, G.; Pardini, L.; Bula, R.; Bettinger, H. F.; Draxl, C.; Chassé, T.; Casu, M. B. Fingerprint of fractional charge transfer at the metal/organic interface. J. Phys. Chem. C 2015, 119, 12538–12544.CrossRefGoogle Scholar
  53. [53]
    Heimel, G.; Duhm, S.; Salzmann, I.; Gerlach, A.; Strozecka, A.; Niederhausen, J.; Bürker, C.; Hosokai, T.; Fernandez-Torrente, I.; Schulze, G. et al. Charged and metallic molecular monolayers through surface-induced aromatic stabilization. Nat. Chem. 2013, 5, 187–194.CrossRefGoogle Scholar
  54. [54]
    Graus, M.; Grimm, M.; Metzger, C.; Dauth, M.; Tusche, C.; Kirschner, J.; Kümmel, S.; Schöll, A.; Reinert, F. Electron–vibration coupling in molecular materials: Assignment of vibronic modes from photoelectron momentum mapping. Phys. Rev. Lett. 2016, 116, 147601.CrossRefGoogle Scholar
  55. [55]
    Savu, S.-A.; Biswas, I.; Sorace, L.; Mannini, M.; Rovai, D.; Caneschi, A.; Chassé, T.; Casu, M. B. Nanoscale assembly of paramagnetic organic radicals on Au(111) single crystals. Chem.—Eur. J. 2013, 19, 3445–3450.CrossRefGoogle Scholar
  56. [56]
    Kakavandi, R.; Ravat, P.; Savu, S. A.; Borozdina, Y. B.; Baumgarten, M.; Casu, M. B. Electronic structure and stability of fluorophore–nitroxide radicals from ultrahigh vacuum to air exposure. ACS Appl. Mater. Interfaces 2015, 7, 1685–1692.CrossRefGoogle Scholar
  57. [57]
    Likhtenshtein, G. I. Novel fluorescent methods for biotechnological and biomedical sensoring: Assessing antioxidants, reactive radicals, NOdynamics, immunoassay, and biomembranes fluidity. Appl. Biochem. Biotechnol. 2009, 152, 135–155.CrossRefGoogle Scholar
  58. [58]
    Wang, H. M.; Zhang, D. Q.; Guo, X. F.; Zhu, L. Y.; Shuai, Z. G.; Zhu, D. B. Tuning the fluorescence of 1-imino nitroxide pyrene with two chemical inputs: Mimicking the performance of an “AND” gate. Chem. Commun. 2004, 670–671.Google Scholar
  59. [59]
    Hughes, B. K.; Braunecker, W. A.; Ferguson, A. J.; Kemper, T. W.; Larsen, R. E.; Gennett, T. Quenching of the perylene fluorophore by stable nitroxide radical-containing macromolecules. J. Phys. Chem. B 2014, 118, 12541–12548.CrossRefGoogle Scholar
  60. [60]
    Diebold, U. The surface science of titanium dioxide. Surf. Sci. Rep. 2003, 48, 53–229.CrossRefGoogle Scholar
  61. [61]
    Jones, F. H. Teeth and bones: Applications of surface science to dental materials and related biomaterials. Surf. Sci. Rep. 2001, 42, 75–205.CrossRefGoogle Scholar
  62. [62]
    Pang, C. L.; Lindsay, R.; Thornton, G. Chemical reactions on rutile TiO2(110). Chem. Soc. Rev. 2008, 37, 2328–2353.CrossRefGoogle Scholar
  63. [63]
    Diebold, U.; Li, S. C.; Schmid, M. Oxide surface science. Annu. Rev. Phys. Chem. 2010, 61, 129–148.CrossRefGoogle Scholar
  64. [64]
    Caneschi, A.; Casu, M. B. Substrate-induced effects in thin films of a potential magnet composed of metal-free organic radicals deposited on Si(111). Chem. Commun. 2014, 50, 13510–13513.CrossRefGoogle Scholar
  65. [65]
    Kakavandi, R.; Savu, S.-A.; Caneschi, A.; Casu, M. B. Paramagnetic character in thin films of metal-free organic magnets deposited on TiO2(110) single crystals. J. Phys. Chem. C 2013, 117, 26675–26679.CrossRefGoogle Scholar
  66. [66]
    Savu, S.-A.; Sonström, A.; Bula, R.; Bettinger, H. F.; Chassé, T.; Casu, M. B. Intercorrelation of electronic, structural, and morphological properties in nanorods of 2,3,9,10-tetrafluoropentacene. ACS Appl. Mater. Interfaces 2015, 7, 19774–19780.CrossRefGoogle Scholar
  67. [67]
    Casu, M. B.; Schuster, B.-E.; Biswas, I.; Raisch, C.; Marchetto, H.; Schmidt, T.; Chassé, T. Locally resolved core-hole screening, molecular orientation, and morphology in thin films of diindenoperylene deposited on Au(111) single crystals. Adv. Mater. 2010, 22, 3740–3744.CrossRefGoogle Scholar
  68. [68]
    Di Valentin, C.; Pacchioni, G.; Selloni, A. Electronic structure of defect states in hydroxylated and reduced rutile TiO2(110) surfaces. Phys. Rev. Lett. 2006, 97, 166803.CrossRefGoogle Scholar
  69. [69]
    Borozdina, Y. B.; Kamm, V.; Laquai, F.; Baumgarten, M. Tuning the sensitivity of fluorophore–nitroxide radicals. J. Mater. Chem. 2012, 22, 13260–13267.CrossRefGoogle Scholar
  70. [70]
    Hesse, R.; Chassé, T.; Streubel, P.; Szargan, R. Error estimation in peak-shape analysis of XPS core-level spectra using UNIFIT 2003: How significant are the results of peak fits? Surf. Interface Anal. 2004, 36, 1373–1383.CrossRefGoogle Scholar
  71. [71]
    Giannozzi, P.; Baroni, S.; Bonini, N.; Calandra, M.; Car, R.; Cavazzoni, C.; Ceresoli, D.; Chiarotti, G. L.; Cococcioni, M.; Dabo, I. et al. Quantum espresso: A modular and open-source software project for quantum simulations of materials. J. Phys.: Condens. Matter 2009, 21, 395502.Google Scholar
  72. [72]
    Vanderbilt, D. Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. Phys. Rev. B 1990, 41, 7892–7895.CrossRefGoogle Scholar
  73. [73]
    Pehlke, E.; Scheffler, M. Evidence for site-sensitive screening of core holes at the Si and Ge(001) surface. Phys. Rev. Lett. 1993, 71, 2338–2341.CrossRefGoogle Scholar

Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Reza Kakavandi
    • 1
  • Arrigo Calzolari
    • 2
  • Yulia B. Borozdina
    • 3
  • Prince Ravat
    • 3
  • Thomas Chassé
    • 1
  • Martin Baumgarten
    • 3
  • M. Benedetta Casu
    • 1
  1. 1.Institute of Physical and Theoretical ChemistryUniversity of TübingenTübingenGermany
  2. 2.CNR-NANO Istituto NanoscienzeModenaItaly
  3. 3.Max Planck Institute for Polymer ResearchMainzGermany

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