The definition of nano-composite material has broadened significantly to encompass a large variety of systems such as one-dimensional, two-dimensional, three-dimensional and amorphous materials, made of distinctly dissimilar components and mixed at the nanometer scale.
The general class of nanocomposite organic/inorganic materials is a fast growing area of research. Significant effort is focused on the ability to obtain control of the nanoscale structures via innovative synthetic approaches. The properties of nano-composite materials depend not only on the properties of their individual parents but also on their morphology and interfacial characteristics.
This rapidly expanding field is generating many exciting new materials with novel properties. The latter can derive by combining properties from the parent constituents into a single material. There is also the possibility of new properties which are unknown in the parent constituent materials.
The inorganic components can be three-dimensional framework systems such as zeolites, two-dimensional layered materials such as clays, metal oxides, metal phosphates, chalcogenides, and even one-dimensional and zero-dimensional materials such as (Mo3Se3-)n chains and clusters. Experimental work has generally shown that virtually all types and classes of nanocomposite materials lead to new and improved properties when compared to their macrocomposite counterparts. Therefore, nanocomposites promise new applications in many fields such as mechanically reinforced lightweight components, non-linear optics, battery cathodes and ionics, nano-wires, sensors and other systems.
The general class of organic/inorganic nanocomposites may also be of relevance to issues of bio-ceramics and biomineralization in which in-situ growth and polymerization of biopolymer and inorganic matrix is occurring. Finally, lamellar nanocomposites represent an extreme case of a composite in which interface interactions between the two phases are maximized. Since the remarkable properties of conventional composites are mainly due to interface interactions, the materials dealt with here could provide good model systems in which such interactions can be studied in detail using conventional bulk sample (as opposed to surface) techniques. By judiciously engineering the polymer-host interactions, nanocomposites may be produced with a broad range of properties.
Inorganic layered materials exist in great variety. They possess well defined, ordered intralamellar space potentially accessible by foreign species. This ability enables them to act as matrices or hosts for polymers, yielding interesting hybrid nano-composite materials.
Lamellar nano-composites can be divided into two distinct classes, intercalated and exfoliated. In the former, the polymer chains alternate with the inorganic layers in a fixed compositional ratio and have a well defined number of polymer layers in the intralamellar space. In exfoliated nano-composites the number of polymer chains between the layers is almost continuously variable and the layers stand >100 Å apart. The intercalated nano-composites are also more compound-like because of the fixed polymer/layer ratio, and they are interesting for their electronic and charge transport properties. On the other hand, exfoliated nano-composites are more interesting for their superior mechanical properties.
Our work focuses on the lamellar class of intercalated organic/inorganic nanocomposites and namely those systems that exhibit electronic properties in at least one of the components. This subclass of nano-composites offers the possibility of obtaining well ordered systems some of which may lead to unusual electrical and mechanical properties. Selected members of this class may be amenable to direct structural characterization by standard crystallographic methods. An important issue in this area is the few structural details that are available, therefore, any system which can be subjected to such analysis is of interest. Nanocomposites also offer the possibility to combine diverse properties which are impossible within a single material, e.g. flexible mechanical properties and superconducting properties. This work is now in its infancy and we propose to carry out extensive investigations in the next funding period. Another exciting aspect is the possibility of creating heterostructures composed of different kinds of inorganic layers, which could lead to new multifuntional materials.
In the past we have focused our efforts on creating such materials with conjugated and saturated organic macromolecules. We have developed several general synthetic routes for inserting polymer chains into host structures and have designed many novel nanocomposites.
- In-situ intercalative polymerization (ISIP) of a monomer using the host itself as the oxidant. The rationale behind intercalative polymerization is that host matrices with high electron affinity can oxidatively polymerize appropriate monomers in their interior.
- Monomer intercalation followed by topotactic intralamellar solid state polymerization. This route creates conjugated polymers inside non-oxidizing hosts.
- Direct precipitative encapsulation of polymer chains by colloidally dispersed single layers of a host. This approach gives access to a large variety of nano-composites with many kinds of polymers and hosts.
"Conductive Polymer Bronzes. Intercalated Polyaniline in V2O5 Xerogels" M.G. Kanatzidis, C.-G. Wu, H.O. Marcy, C.R. Kannewurf J. Am. Chem. Soc., 1989, 111, 4139-4141
- "Conductive-Polymer Intercalation in Layered V2O5 Xerogels. Intercalated Polypyrrole" C.-G. Wu, M.G. Kanatzidis, H.O. Marcy, D.C. DeGroot, C.R. Kannewurf Polym. Mat. Sci. Eng. 1989, 61, 969-973.
- "Low-Dimensional Electrically Conductive Systems. Intercalated Polymers in V2O5 Xerogels" C.-G. Wu, M.G. Kanatzidis, H.O. Marcy, D.C. DeGroot, C.R. Kannewurf NATO-ASI "Lower-Dimensional Systems and Molecular Devices" R.M. Metzger Ed. Plenum Press, Inc. 1991, 427-434.
- "V2O5 Xerogels as Hosts for Conductive Polymers. Intercalative Polymerization of Aniline, Pyrrole and 2,2'-Bithiophene" C.-G. Wu, H. O. Marcy, D. C. DeGroot and C. R. Kannewurf, M. G. Kanatzidis Mat. Res. Soc. Symp. Proc. 1990, 173, 317-322
- "Conductive-Polymer/Bronze Nanocomposites. Intercalated Polythiophene in V2O5 Xerogels" M. G. Kanatzidis, C.-G. Wu, H. O. Marcy, D. C. DeGroot and C. R. Kannewurf Chem. of Mater. 1990, 2, 222-224
- "Intercalation Chemistry of Conductive Polymers. New Crystalline Microlaminate Phases in the Polyaniline/FeOCl System." M. G. Kanatzidis, C.-G. Wu, H. O. Marcy, D. C. DeGroot, C. R. Kannewurf, A. Kostikas and V. Papaefthymiou Advanced Materials , 1990, 2, 364-366
- "Polymeric Electrical Conductors" M. G. Kanatzidis Chemical and Engineering News, 1990, December issue, pp 36-54
- "Oxidative Polymerization of Pyrrole and Aniline in Hofmann-Type Inclusion Compounds" C.-G. Wu, H. O. Marcy, D. C. DeGroot J. L. Schindler, C. R. Kannewurf and M. G. Kanatzidis Synthetic Metals, 1991, 41/43, 693-698
- "Intercalation of Polyfuran in FeOCl" C.-G. Wu, H. O. Marcy, D. C. DeGroot, J. L. Schindler, C. R. Kannewurf, W.-Y. Leung, M. Benz, E. LeGoff and M. G. Kanatzidis Synthetic Metals, 1991, 41/43, 797-803
- "Layered V2O5 Xerogels: Host-Guest Chemistry and Conductive Polymers" C.-G. Wu and M. G. Kanatzidis. Symposium on "Solid State Ionics" G. Nazri, R. A. Huggins, D. F. Shriver, M. Balkanski Editors.MRS Symp. Proc. 1991, 210, 429-442
- "Crystalline Inorganic Hosts as Media for the Synthesis of Conductive Polymers" M. G. Kanatzidis, C.-G. Wu, H. O. Marcy, D. C. DeGroot, J. L. Schindler, C. R. Kannewurf, M. Benz and E. LeGoff "Supramolecular Chemistry in Two and Three Dimensions" T. Bein Ed. ACS Symposium Series 1992, 499, 194-219
- "Intercalation of Layered V2O5 Xerogel with Polymers" M. G. Kanatzidis, C.-G. Wu, Y.-J. Liu, D. C. DeGroot, J. L. Schindler, H. O. Marcy, C. R. Kannewurf in "Synthesis/ Characterization and Novel Applications of Molecular Sieve Materials" Bedard, Bein, Davis, Garces, Maroni, Stucky: Editors, Mat. Res. Soc. Symp. Proc. 1991, 233, 183-194
- "Intercalation of Polyethylene-Oxide in V2O5 Xerogel" Y.-J. Liu, D. C. DeGroot, J. L. Schindler, C. R. Kannewurf, M. G. Kanatzidis Chem Mater. 1991, 3, 992-994
- "Charge Transport and Optical Properties of the First Highly Conductive One-Dimensional Molecular Metal Containing Fluoride Counterions: (TSeT)F0.25Cl0.50" J. A. Schlueter, Y. Orihashi, M. G. Kanatzidis, W. Liang, T. J. Marks, D. C. DeGroot, H. O. Marcy, W. J. McCarthy, C. R. Kannewurf, T. Inabe Chem Mater. 1991, 3, 1013-1015
- "Phonon Studies of Intercalated Conductive Polymers" K. Prassides, C. Bell, A. J. Dianoux, C.-G. Wu, M. G. Kanatzidis Physica B 1992, 180&181, 668-670
- "Variable Frequency Conductivity of Layered Polypyrrole/V2O5 Composites" D. C. DeGroot, J. L. Schindler, C. R. Kannewurf, Y.-J. Liu, C. G. Wu, M. G. Kanatzidis in "Submicron Multiphase Materials" Baney, R.; Gilliom, L.; Schmidt, H.; Hirano, S.-I. Eds Mat. Res. Soc. Symp. Proc. 1992, 234-240
- "Conjugated Polymers in Layered Hosts. Formation of Emeraldine Salt and Polyfuran in FeOCl" M. G. Kanatzidis, C.-G. Wu, D. C. DeGroot, J. L. Schindler, M. Benz and E. LeGoff, C. R. Kannewurf, Chapter in "Chemical Physics of Intercalation II" NATO-ASI , P. Bernier, J. E. Fisher, S. Roth, S. A. Solin, Editors, Plenum Press, New York, 1993, pp 63-72
- "Stabilization of Anilinium in V2O5 Xerogel and its Post-Intercalative Polymerization to Polyaniline in Air" Y.-J. Liu, D. C. DeGroot, J. L. Schindler, C. R. Kannewurf, M. G. Kanatzidis, J. Chem. Soc. Chem. Commun. 1993, 593-596
- "Inclusion of Polyaniline into MoO3" R. Bissessur, D. C. DeGroot, J. L. Schindler, C. R Kannewurf and M. G. Kanatzidis J. Chem. Soc. Chem. Commun. 1993, 687-689
- "Intercalation of Water-Soluble Polymers in V2O5 Xerogel" Y.-J. Liu, D. C. DeGroot, J. L. Schindler, C. R. Kannewurf and M. G. Kanatzidis Advanced Materials 1993, 5, 369-372
- "On Polyfuran: A New Synthetic Approach and Electronic Properties" S. Glenis, M. Benz, E. LeGoff, J. L. Schindler, C. R. Kannewurf and M. G. Kanatzidis J. Am. Chem. Soc. 1993, 115, 12519-12525
- "Topotactic Solid-State Polymerization of Aniline in Layered Uranyl Phosphate" Y.-J. Liu and M. G. Kanatzidis, Inorg. Chem. 1993, 32, 2989-2991
- "New Intercalation Compounds of Conjugated Polymers. Encapsulation of Polyaniline in MoS2." M. G. Kanatzidis, R. Bissessur, D. C. DeGroot, J. L. Schindler, C. R. Kannewurf and , Chem. Mater. 1993, 5, 595-596
- "Nanoscale Composites Formed by Encapsulation of Polymers in MoS2. From Conjugated Polymers to Plastics. Detection of Metal to Insulator Transition." R. Bissessur, J. L. Schindler, C. R. Kannewurf and Mercouri Kanatzidis, Mol. Cryst. Liq. Cryst. 1993, 245, 249-254
- "Encapsulation of Polymers into MoS2 and Metal to Insulator Transition in Metastable MoS2" R.Bissessur, M, Kanatzidis, J. L. Schindler and C. R. Kannewurf, J. Chem. Soc. Chem. Commun. 1993, 1582-1585
- "Oligothiophenes as Models for Polythiophenes. The Crystal and Molecular Structures of 3'',4''-dibutyl-pentathiophene and 3',3'''',4',4''''-tetrabutyl-hexathiophene. Structural Implications for Conjugated Polymers." Ju-Hsiou Liao, Michael Benz, Eugene LeGoff and Mercouri G. Kanatzidis Adv. Mater. 1994, 6, 135-138
- "Post-Intercalative Polymerization of Aniline and its Derivatives in Layered Metal Phosphates" Yu-Ju Liu and Mercouri G. Kanatzidis Chem. Mater. 1995, 7, 1525-1533
- "Reaction of Aniline with FeOCl. Formation and Ordering of Conducting Polyaniline in a Crystalline Layered Host" C.-G. Wu, D. C. DeGroot, H. O. Marcy, J. L. Schindler, C. R. Kannewurf, T. Bakas, V. Papaefthymiou, W. Hirpo, J. P. Yesinowski, Y.-J. Liu, M. G. Kanatzidis, J. Am. Chem. Soc. 1995, 117, 9229-9242.
- "Entrapment of Polypyrrole Chains Between MoS2 Layers Via an In-situ Oxidative Polymerization Encapsulation Reaction." Lei Wang, Jon Schindler, Joyce Albritton Thomas, Carl R. Kannewurf and Mercouri G. Kanatzidis Chemistry of Materials 1995, 7, 1753-1755.
- "Towards Pillared Layered Metal-Sulfides. Intercalation of the Chalcogenide Clusters Co6Q8(PR3)6 (Q=S, Se and Te and R = alkyl) into MoS2" Rabin Bissessur, Joy Heising, Wakgari Hirpo and Mercouri Kanatzidis, Chem. Mater. , 1996, 8, 318-320.
- "Synthesis, Structure and Reactions of Poly(ethylene-oxide)V2O5 Intercalative Nano-composites" Y.-J. Liu, J. L. Schindler, D. C. DeGroot, C. R. Kannewurf, W. Hirpo, M. G. Kanatzidis, Chem. Mater. , 1996, 8, 525-534.
- "Redox Intercalative Polymerization of Aniline in V2O5 Xerogel. The Post-Intercalative Intralamellar Polymer Growth in Polyaniline/Metal-Oxide Nanocomposites is Facilitated by Molecular Oxygen" C.-G. Wu, D. C. DeGroot, H. O. Marcy, J. L. Schindler, C. R. Kannewurf, Y.-J. Liu, Hirpo, W., M. G. Kanatzidis, Chemistry of Materials, 1996, 8, 1992-2004.
- "Plastic Superconducting Polymer- NbSe2 Nanocomposites" Hui-Lien Tsai, Jon L. Schindler, Carl R. Kannewurf and Mercouri G. Kanatzidis, Chem. Mater. 1997, 9, 875-878.
- "Lamellar Polymer-LixMoO3 Nanocomposites Via Encapsulative Precipitation" Lei Wang, Jon Schindler, Carl R. Kannewurf, Mercouri G. Kanatzidis, J. Mater. Chem., 1997, 7, 1277-1283.
- "Microstructural Characterization of Highly HDS-Active Co6S8-Pillared Molybdenum Sulfides" J. Brenner, C. Marshall, L. Ellis, N. Tomczyk, J. Heising and M. G. Kanatzidis, Chem. Mater. , 1998, 10, 1244-1257.
- "a -RuCl3: A New Host for Polymer Intercalation. Lamellar Polymer/RuCl3 Nanocomposites" L. Wang, P. Brazis, M. Rocci, C. R. Kannewurf, M. G. Kanatzidis, in "Organic/Inorganic Hybrid Materials" Eds. R. M. Laine, C. Sanchez, C. J. Brinker, E. Giannelis, Mat. Res. Soc. Symp. Proc., 1998, Vol. 519, 257-264.
- Mesostructured Non-Oxidic Solids with Adjustable Worm-hole Shaped Pores: Metal Germanium Sulfide and Selenide Frameworks Based on the Tetrahedral [Ge4Q10]4- Clusters. Michael Wachhold, K. Kasthuri Rangan, Simon J. L. Billinge, Valeri Petkov, Joy Heising and Mercouri G. Kanatzidis, Advanced Mater. 2000, 12, 85-91.
- "a -RuCl3/Polymer Nanocomposites: the First Group of Intercalative Nanocomposites with Transition-Metal-Halides" Lei Wang, Melissa Rocci-Lane, Paul Brazis, Carl R. Kannewurf, Young-Il Kim, Woo Lee, Jin-Ho Choy And Mercouri G Kanatzidis, J. Am. Chem. Soc., 2000, 122, 6629-6640.