Liquid crystal templates for nanostructured metals

Krieger, K. Judd, C. Simpson, E. Berliner, to the generation of ordered, porous metal nanostructures and J. Dehaan, H. Brown, J. Hill, ihid. Bassindale, reduction of platinum salts dissolved within the aqueous domains P. Patai, 2. Kaufmann, Y Apeloig, V. Braude, D. Danovich, A. Stamatis, AnFew. Prakash, V. Reddy, G. Rasul, J. Casanova, G.

Olah, um tetrachloroplatinate ATCP as the platinum source. The J. Dallaire, M. Brook, Organomefallics lyotropic liquid-crystalline phases were prepared from Kresge,J Am. Eisch, J. Attard, Dr. Templer Department of Chemistry. We also thank Dr. Schaaf for carrying out the TGA measurements. ATCP was reduced by bringing a ternary mixture of surfactant, water, and hydrazine hydrate mixture A into contact with a ternary system containing the metal salt mixture B. Optical mi- zyxwvutsrqpo croscopy revealed that both mixtures A and B were hexagonal zyx mesophases when brought into contact.

Immediate reaction - caused the system to turn black. Ther- Figure 2. The "C in air. Scanning electron microscopy SEM; see Fig- ure 1, top of the dried powder showed that the product com- low-angle scattering and broadening of the diffraction peak in- prised particles nm in diameter. The presence of only one scattering peak in the diffrac- togram is probably due to a low degree of long-range order, which could be caused by nonuniform wall thickness.

Wide-an- gle X-ray diffractograms showed the material to be polycrys- talline with a face-centered cubic fcc structure.

The extended X-ray absorption fine structure EXAFS["' data obtained for the platinum L,,, edge of the nanostructured material see Figure 3 are entirely consistent with the presence of pure platinum metal.

Backscattering shells due to platinurn are observed out to about 5. The material was suspended in acetone, sonicated platinum foil solid and H,-platinum. For clarity, the amplitude of the curve for for 5 min and applied to a carbon-coated copper grid. The best fit to the EXAFS data was nal nanostructure consisting of cylindrical 30 8, diameter achieved with four shells of platinum atoms at 2.

These distances compare well with those pore-to-pore distance of 60 8,. TEM studies of ultramicrotomed observed for bulk platinum metal. Furthermore, the coordina- samples confirmed that this internal nanostructure was also tion numbers of 7, 3, 13, and 7 for the four shells indicate an fcc present in larger particles.

The wall thickness of the nanostruc- structure, which is in good agreement with the wide-angle X-ray tured metal HI-Pt appears to be larger than that of the corre- diffraction results. The lower amplitude and the O-U! SO10 Angept. Structural parameters for H,-platiiiuni and platinum foil. OlXO 6 P. J Ying, Curr. An addi- tional effect of the larger number of surface atoms is an appar- ent shortening of the metal-metal bonds relative to those of the bulk metal. A separate series of experiments employed lower surfactant C.

Goltner, M. Antonictti, A h. Leonowicz, W. Roth, J. Beck, Nature , , ; b J. Beck, J. Vartuli, W. Lconowicz, C. Kresge, K. Schmitt; C. Sheppard, S. B Higgins. I A m Chen7. Huo, D. Ciesla, P. Feng, T E. Sieger, R. Petroff, F. Schuth, G. Cheng, Z Luan, J. Klinowski, Lur? I I , ; e 1. Liu, A. Kim, J. Virden, B. C Bunker. Attard, J. Glyde, C. G Goltncr. Edgar, C G. Thus, these materials may have application in extra-sensitive, repeatable surface-enhanced Raman spectroscopy.

The present method provides a way not only to fabricate ordered mesoporous metals in confined nanosystem, but also to control the geometry, orientation and structures. We expect that this work can help to establish a new mechanistic understanding of the formation of metal mesostructures and may be generalized to the LLC templating synthesis of other materials. Erlebacher, J.

Evolution of nanoporosity in dealloying. Nature , — Charge-induced reversible strain in a metal. Science , — Lefebvre, L. Porous metals and metallic foams: current status and recent developments.

Warren, S. Ordered mesoporous materials from metal nanoparticles-block copolymer self-assembly. Yamauchi, Y. Rational design of mesoporous metals and related nanomaterials by a soft-template approach. Asian J. Wu, Y. Composite mesostructures by nano-confinement. Nature Mater. Li, C. Electrochemical synthesis of one-dimensional mesoporous Pt nanorods using the assembly of surfactant micelles in confined space. Fujita, T. Atomic origins of the high catalytic activity of nanoporous gold.

Chan, S. Surface-enhanced Raman scattering of small molecules from silver-coated silicon nanopores. Baumberg, J. Angle-resolved surface-enhanced Raman scattering on metallic nanostructured plasmonic crystals. Nano Lett. Unusually small electrical resistance of three-dimensional nanoporous gold in external magnetic fields.

Biener, J. Nanoporous plasmonic metamaterials. Yu, F. Simultaneous excitation of propagating and localized surface plasmon resonance in nanoporous gold membranes. Kresge, C. Ordered mesoporous molecular-sieves synthesized by a liquid-crystal templating mechanism. Beck, J. A new family of mesoporous molecular-sieves prepared with liquid-crystal templates.

Johnson, S. Ordered mesoporous polymers of tunable pore size from colloidal silica templates. Zhao, D. Triblock copolymer syntheses of mesoporous silica with periodic 50 to angstrom pores. Braun, P. Macroscopic nanotemplating of semiconductor films with hydrogen-bonded lyotropic liquid crystals. Attard, G. Mesoporous platinum films from lyotropic liquid crystalline phases. Liquid-crystal templates for nanostructured metals. Brinker, C.

Evaporation-induced self-assembly: Nanostructures made easy. Self-assembled ordered mesoporous metals. Pure Appl. Langmuir 14, — Takai, A. Tailored electrochemical synthesis of 2D-hexagonal, lamellar and cage-type mesostructured Pt thin films with extralarge periodicity. Pt fibers with stacked donut-like mesospace by assembling Pt nanoparticles: guided deposition in physically confined self-assembly of surfactants.

Zhang, X. Ordered hierarchical porous platinum membranes with tailored mesostructures. Adams, N. Seismic design rules for flat bottom cylindrical liquid storage tanks. Article Google Scholar. Wang, Z. Transmission electron microscopy of shape-controlled nanocrystals and their assemblies. B , — Production of monodispersed colloidal particles.

Mitchell, D. Phase-behavior of polyoxyethylene surfactants with water-mesophase structures and partial miscibility cloud points. Faraday Trans. Miller, C. Solubilization emulsification mechanisms of detergency.

Colloids Surf. A 74, — Surface effects and anchoring in liquid-crystals. Crawford, G. Surface-induced orientational order in the isotropic-phase of a liquid-crystal material. A 44, — Shahidzadeh, N. Jayasri, D. Liquid crystal films on curved surfaces: An entropic sampling study.

Physica A , — Oliveira, E. Anchoring properties of lyotropic liquid crystals near the nematic-isotropic transition. E 49, Bakshi, M. Association behavior of poly ethylene oxide -polypropylene oxide poly ethylene oxide block copolymers with cationic surfactants in aqueous solution.

Colloid Interf. Miao, J. Micropumps based on the enhanced electroosmotic effect of aluminum oxide membranes. Ordering and self-diffusion in the first molecular layer at a liquid-crystal-polymer interface. Markovic, N. Kinetics of oxygen reduction on Pt hkl electrodes: Implications for the crystallite size effect with supported Pt electrocatalysts.

Grgur, B. Temperature dependent oxygen electrochemistry on platinum low index single crystal surfaces in acid solutions. Liu, H. Download references.

The authors acknowledge use of facilities within the Monash Centre for Electron Microscopy. You can also search for this author in PubMed Google Scholar. All the authors discussed the results and commented on the manuscript. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder in order to reproduce the material.

Reprints and Permissions. Nanofabrication of highly ordered, tunable metallic mesostructures via quasi-hard-templating of lyotropic liquid crystals. Sci Rep 4, Download citation. Received : 07 November Accepted : 14 November Published : 11 December Anyone you share the following link with will be able to read this content:.

Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative.

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate. Advanced search. Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily. Skip to main content Thank you for visiting nature.