Skip to main content
SpringerLink
Log in

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

  • Research Article
  • Published:
Nano Research Aims and scope Submit manuscript

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.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Getzlaff, M. Fundamentals of Magnetism; Springer-Verlag: Berlin, Heidelberg, 2008.

    Google Scholar 

  2. Gatteschi, D.; Sessoli, R.; Villain, J. Molecular Nanomagnets; Oxford University Press: New York, 2006.

    Book  Google Scholar 

  3. Nobelprize.org. The Nobel Prize in Physics 2007 [Online]. http://www.nobelprize.org/nobel_prizes/physics/laureates/2 007/(accessed Jul 14, 2016).

  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.

    Article  Google Scholar 

  5. Sanvito, S. Molecular spintronics. Chem. Soc. Rev. 2011, 40, 3336–3355.

    Article  Google Scholar 

  6. Miller, J. S. Magnetically ordered molecule-based materials. Chem. Soc. Rev. 2011, 40, 3266–3296.

    Article  Google Scholar 

  7. Epifanov, G. I. Solid State Physics; Mir Publisher: Moscow, 1979.

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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. 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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  13. Hicks, R. G. Stable Radicals: Fundamentals and Applied Aspects of Odd-Electron Compounds; Wiley: Chichester, 2010.

  14. Rajca, A.; Shiraishi, K.; Pink, M.; Rajca, S. Triplet (S = 1) ground state aminyl diradical. J. Am. Chem. Soc. 2007, 129, 7232–7233.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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. Caneschi, A.; Gatteschi, D.; Sessoli, R.; Rey, P. Toward molecular magnets: The metal-radical approach. Acc. Chem. Res. 1989, 22, 392–398.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  19. Ratera, I.; Veciana, J. Playing with organic radicals as building blocks for functional molecular materials. Chem. Soc. Rev. 2012, 41, 303–349.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  30. Tomlinson, E. P.; Hay, M. E.; Boudouris, B. W. Radical polymers and their application to organic electronic devices. Macromolecules 2014, 47, 6145–6158.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  32. Oyaizu, K.; Nishide, H. Radical polymers for organic electronic devices: A radical departure from conjugated polymers? Adv. Mater. 2009, 21, 2339–2344.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  40. Rajca, A. Organic diradicals and polyradicals: From spin coupling to magnetism? Chem. Rev. 1994, 94, 871–893.

    Google Scholar 

  41. Blatter, H. M.; Lukaszewski, H. A new stable free radical. Tetrahedron Lett. 1968, 9, 2701–2705.

  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.

    Article  Google Scholar 

  43. Lüth, H. Solid Surfaces, Interfaces and Thin Films; Springer: Berlin, Heidelberg, 2010.

  44. Sanvito, S. Molecular spintronics: The rise of spinterface science. Nat. Phys. 2010, 6, 562–564.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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. 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.

    Article  Google Scholar 

  60. Diebold, U. The surface science of titanium dioxide. Surf. Sci. Rep. 2003, 48, 53–229.

    Article  Google Scholar 

  61. Jones, F. H. Teeth and bones: Applications of surface science to dental materials and related biomaterials. Surf. Sci. Rep. 2001, 42, 75–205.

    Article  Google Scholar 

  62. Pang, C. L.; Lindsay, R.; Thornton, G. Chemical reactions on rutile TiO2(110). Chem. Soc. Rev. 2008, 37, 2328–2353.

    Article  Google Scholar 

  63. Diebold, U.; Li, S. C.; Schmid, M. Oxide surface science. Annu. Rev. Phys. Chem. 2010, 61, 129–148.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  69. Borozdina, Y. B.; Kamm, V.; Laquai, F.; Baumgarten, M. Tuning the sensitivity of fluorophore–nitroxide radicals. J. Mater. Chem. 2012, 22, 13260–13267.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

  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. Vanderbilt, D. Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. Phys. Rev. B 1990, 41, 7892–7895.

    Article  Google Scholar 

  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.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Institute of Physical and Theoretical Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany

    Reza Kakavandi, Thomas Chassé & M. Benedetta Casu

  2. CNR-NANO Istituto Nanoscienze, Centro S3, 41125, Modena, Italy

    Arrigo Calzolari

  3. Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany

    Yulia B. Borozdina, Prince Ravat & Martin Baumgarten

Authors
  1. Reza Kakavandi
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Arrigo Calzolari
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yulia B. Borozdina
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Prince Ravat
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Thomas Chassé
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Martin Baumgarten
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. M. Benedetta Casu
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to M. Benedetta Casu.

Additional information

These authors contributed equally to this work.

Electronic supplementary material

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kakavandi, R., Calzolari, A., Borozdina, Y.B. et al. Unraveling the mark of surface defects on a spinterface: The nitronyl nitroxide/TiO2(110) interface. Nano Res. 9, 3515–3527 (2016). https://doi.org/10.1007/s12274-016-1228-1

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12274-016-1228-1

Keywords

Search

Navigation