Abstract
The immense potential of colossal permittivity (CP) materials for use in modern microelectronics as well as for high-energy-density storage applications has propelled much recent research and development. Despite the discovery of several new classes of CP materials, the development of such materials with the required high performance is still a highly challenging task. Here, we propose a new electron-pinned, defect-dipole route to ideal CP behaviour, where hopping electrons are localized by designated lattice defect states to generate giant defect-dipoles and result in high-performance CP materials. We present a concrete example, (Nb+In) co-doped TiO2 rutile, that exhibits a largely temperature- and frequency-independent colossal permittivity (> 104) as well as a low dielectric loss (mostly < 0.05) over a very broad temperature range from 80 to 450 K. A systematic defect analysis coupled with density functional theory modelling suggests that ‘triangular’ In23+VO••Ti3+ and ‘diamond’ shaped Nb25+Ti3+ATi (A = Ti3+/In3+/Ti4+) defect complexes are strongly correlated, giving rise to large defect-dipole clusters containing highly localized electrons that are together responsible for the excellent CP properties observed in co-doped TiO2. This combined experimental and theoretical work opens up a promising feasible route to the systematic development of new high-performance CP materials via defect engineering.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Homes, C. C., Vogt, T., Shapiro, S. M., Wakimoto, S. & Ramirez, A. P. Optical response of high-dielectric-constant perovskite-related oxide. Science 293, 673–676 (2001).
Krohns, S. et al. The route to resource-efficient novel materials. Nature Mater. 10, 899–901 (2011).
Ikeda, N. et al. Ferroelectricity from iron valence ordering in the charge-frustrated system LuFe2O4 . Nature 436, 1136–1138 (2005).
Shu-Nan, M. & Maki, M. Dielectric anisotropy in the charge-density-wave state of K0.3MoO3 . J. Phys. Soc. Jpn 80, 084706 (2011).
Hess, H. F., Deconde, K., Rosenbaum, T. F. & Thomas, G. A. Giant dielectric constants at the approach to the insulator-metal transition. Phys. Rev. B 25, 5578–5580 (1982).
Wang, C. C. & Zhang, L. W. Surface-layer effect in CaCu3Ti4O12 . Appl. Phys. Lett. 88, 042906 (2006).
Subramanian, M. A., Li, D., Duan, N., Reisner, B. A. & Sleight, A. W. High dielectric constant in ACu3Ti4O12 and ACu3Ti3FeO12 phases. J. Solid State Chem. 151, 323–325 (2000).
Wu, J. B., Nan, C. W., Lin, Y. H. & Deng, Y. Giant dielectric permittivity observed in Li and Ti doped NiO. Phys. Rev. Lett. 89, 217601 (2002).
Krohns, S. et al. Colossal dielectric constant up to gigahertz at room temperature. Appl. Phys. Lett. 94, 122903 (2009).
Lunkenheimer, P. et al. Origin of apparent colossal dielectric constants. Phys. Rev. B 66, 052105 (2002).
Sarkar, S., Jana, P. K. & Chaudhuri, B. K. Colossal internal barrier layer capacitance effect in polycrystalline copper (II) oxide. Appl. Phys. Lett. 92, 022905 (2008).
Lunkenheimer, P. et al. Colossal dielectric constants in transition-metal oxides. Eur. Phys. J. 180, 61–89 (2010).
Buscaglia, M. T. et al. High dielectric constant and frozen macroscopic polarization in dense nanocrystalline BaTiO3 ceramics. Phys. Rev. B 73, 064114 (2006).
Ramirez, A. P. et al. Giant dielectric constant response in a copper-titanate. Solid State Commun. 115, 217–220 (2000).
Li, M., Feteira, A., Sinclair, D. C. & West, A. R. Influence of Mn doping on the semiconducting properties of CaCu3Ti4O12 ceramics. Appl. Phys. Lett. 88, 232903 (2006).
Liu, Y., Withers, R. L. & Wei, X. Y. Structurally frustrated relaxor ferroelectric behavior in CaCu3Ti4O12 . Phys. Rev. B 72, 134104 (2005).
Zhu, Y. et al. Nanoscale disorder in CaCu3Ti4O12: A new route to the enhanced dielectric response. Phys. Rev. Lett. 99, 037602 (2007).
Zhang, L. & Tang, Z. J. Polaron relaxation and variable-range-hopping conductivity in the giant-dielectric-constant material CaCu3Ti4O12 . Phys. Rev. B 70, 174306 (2004).
Krohns, S., Lunkenheimer, P., Ebbinghaus, S. G. & Loidl, A. Colossal dielectric constants in single-crystalline and ceramic CaCu3Ti4O12 investigated by broadband dielectric spectroscopy. J. Appl. Phys. 103, 084107 (2008).
Guillemet-Fritsch, S. et al. Colossal permittivity in ultrafine grain size BaTiO3−x and Ba0.95La0.05TiO3−x materials. Adv. Mater. 20, 551–555 (2008).
Jonscher, A. K. The universal dielectric response. Nature 267, 673–679 (1977).
Whangbo, M. H. & Subramanian, M. A. Structural model of planar defects in CaCu3Ti4O12 exhibiting a giant dielectric constant. Chem. Mater. 18, 3257–3260 (2006).
Wuttig, M. et al. The role of vacancies and local distortions in the design of new phase-change materials. Nature Mater. 6, 122–128 (2007).
Balke, N. et al. Enhanced electric conductivity at ferroelectric vortex cores in BiFeO3 . Nature Phys. 8, 81–88 (2012).
Zheng, J. C. et al. Nanoscale disorder and local electronic properties of CaCu3Ti4O12: An integrated study of electron, neutron, and X-ray diffraction, X-ray absorption fine structure, and first-principles calculations. Phys. Rev. B 81, 144203 (2010).
Morgan, B. J. & Watson, G. W. A density functional theory plus U study of oxygen vacancy formation at the (110), (100), (101), and (001) surfaces of rutile TiO2 . J. Phys. Chem. C 113, 7322–7328 (2009).
Parker, R. A. Static dielectric constant of rutile (TiO2), 1.6–1060 K. Phys. Rev. 124, 1719–1722 (1961).
Jonscher, A. K. Universal Relaxation Law (Chelsea Dielectrics, 1996).
Morris, D. et al. Photoemission and STM study of the electronic structure of Nb-doped TiO2 . Phys. Rev. B 61, 13445–13457 (2000).
Li, G. S., Boerio-Goates, J., Woodfield, B. F. & Li, L. P. Evidence of linear lattice expansion and covalency enhancement in rutile TiO2 nanocrystals. Appl. Phys. Lett. 85, 2059–2061 (2004).
Ramos-Moore, E., Ferrari, P., Diaz-Droguett, D. E., Lederman, D. & Evans, J. T. Raman and X-ray photoelectron spectroscopy study of ferroelectric switching in Pb(Nb,Zr,Ti)O3 thin films. J. Appl. Phys. 111, 014108 (2012).
Valigi, M. et al. A structural, thermogravimetric, magnetic, electron spin resonance, and optical reflectance study of the NbOx–TiO2 system. J. Solid State Chem. 77, 255–263 (1988).
Khomenko, V. M., Langer, K., Rager, H. & Fett, A. Electronic absorption by Ti3+ ions and electron delocalization in synthetic blue rutile. Phys. Chem. Miner. 25, 338–346 (1998).
Deford, J. W. & Johnson, O. W. Electron transport properties in rutile from 6 to 40 K. J. Appl. Phys. 54, 889–897 (1983).
Janotti, A., Franchini, C., Varley, J. B., Kresse, G. & Van de Walle, C. G. Dual behavior of excess electrons in rutile TiO2 . Phys. Status Solidi Rapid Res. Lett. 7, 199–203 (2013).
Yu, J. D. et al. Giant dielectric constant of hexagonal BaTiO3 crystal grown by containerless processing. Chem. Mater. 16, 3973–3975 (2004).
Kimura, T., Sekio, Y., Nakamura, H., Siegrist, T. & Ramirez, A. P. Cupric oxide as an induced-multiferroic with high- TC . Nature Mater. 7, 291–294 (2008).
Sheng, Z., Nakamura, M., Kagawa, F., Kawasaki, M. & Tokura, Y. Dynamics of multiple phases in a colossal-magnetoresistive manganite as revealed by dielectric spectroscopy. Nature Commun. 3, 944 (2012).
Blochl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).
Perdew, J. P. et al. Atoms, molecules, solids, and surfaces: Applications of the generalized gradient approximation for exchange and correlation. Phys. Rev. B 46, 6671–6687 (1992).
Dudarev, S. L., Botton, G. A., Savrasov, S. Y., Humphreys, C. J. & Sutton, A. P. Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+U study. Phys. Rev. B 57, 1505–1509 (1998).
Monkhorst, H. J. & Pack, J. D. Special points for Brillouin-zone integrations. Phys. Rev. B 13, 5188–5192 (1976).
Glassford, K. M. & Chelikowsky, J. R. Structural and electronic properties of titanium dioxide. Phys. Rev. B 46, 1284–1298 (1992).
Acknowledgements
W.H., Y.L., R.L.W., A.S. and J.W.L. acknowledge the supports of the Australian Research Council (ARC) in the form of Discovery and Linkage Projects, and of the Australian National University Connect Ventures in the form of Discovery Translation Fund. Y.L. and T.J.F. also appreciate support from the ARC Future Fellowships program. The DFT calculations performed in this work were undertaken using the NCI National Facility in Canberra, Australia, which is supported by the Australian Commonwealth Government. The authors acknowledge AMMRF facilities.
Author information
Authors and Affiliations
Contributions
W.H., Y.L., R.L.W. and T.J.F. contributed to the preparation of manuscript. Y.L. initiated this research, and planned and coordinated all experimental works. Y.L. and R.L.W. were involved in all discussions regarding the data interpretation, structural analyses and development of the defect model. W.H., A.S. and M.K. were involved in the fabrication of the samples with different compositions and synthesizing conditions. W.H. conducted the characterization of the dielectric and conductive properties. W.H. and P.S. performed EPR measurement and analysis. W.H. and B.G. carried out XPS measurement and analysis. T.J.F. performed the DFT calculation and defect modelling. L.N. contributed to the defect design. J.S. contributed to the discussion about the defect model. W.H. carried out the microstructural analysis via SEM with backscattering image and a careful EDX analysis with the assistance of H.C. and F.B. W.H., J.W-L. and Y.L. carried out the dielectric measurements down to ~ 10 K.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Supplementary Information
Supplementary Information (PDF 1935 kb)
Rights and permissions
About this article
Cite this article
Hu, W., Liu, Y., Withers, R. et al. Electron-pinned defect-dipoles for high-performance colossal permittivity materials. Nature Mater 12, 821–826 (2013). https://doi.org/10.1038/nmat3691
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/nmat3691
This article is cited by
-
Tuning enhanced dielectric properties of (Sc3+–Ta5+) substituted TiO2 via insulating surface layers
Scientific Reports (2024)
-
Effects of multiple cations and sintering temperature on microstructure and dielectric properties in Na1/2Ln1/2Cu3Ti4O12 (Ln = Sm and Eu) ceramic materials
Scientific Reports (2023)
-
Point-defect-driven flattened polar phonon bands in fluorite ferroelectrics
npj Computational Materials (2023)
-
Permittivity boosting by induced strain from local doping in titanates from first principles
Scientific Reports (2023)
-
Machine learning and atomistic origin of high dielectric permittivity in oxides
Scientific Reports (2023)