Department of Materials and Interfaces

David Cahen, Head


The scientific research of the department focuses on the understanding and design of functional materials with unique physical and chemical properties. This includes a broad range of materials, such as solids with extended bonding displaying cooperative properties (dielectric and opto-electronic materials); nanomaterials, like carbon and inorganic nanotubes; ultra thin pyro-electric films; solids and liquids with mainly molecular bonding, such as complex fluids and molecular crystals; ultra-thin organic, inorganic and biological films and assemblies; size-quantized nanoparticles and fulleroids; molecularly functionalized semiconductors and metals, also for (bio)sensors and for (bio)molecular electronics; polymers, including polymer brushes and polymers for cloud seeding; and nanocomposites displaying unique mechanical properties. Biopolymer mechanics and molecular transport phenomena in the cell are studied, also for imitation of biological transport strategies. Further activities include solar cell (photovoltaic) materials and device structures and planned self-assembly of novel nanostructures on scanning-probe-patterned organic monolayer templates. Several new research groups have been established over the last few years in the areas of carbon nanotubes and scanning probe microscopy, of mechanisms of biological transcription on Si chips, using microfabrication and microfluidics, in computational materials research, a group that focuses on to the study of clusters, magnetic nanoparticles, nanocrystalline materials, inorganic-organic interfaces and optical phenomena in semiconductors and one in the general area of elastic effects in the chemistry of materials, that focuses on nanocrystalline electroceramic films, and quasi-amorphous ceramic films.
Several groups in the department are developing novel theoretical and experimental methodologies for probing interfaces between liquids, solids and gases. These include force measurement techniques at sub-nanometer surface separation; nanomechanical testing of nanotubes; electrochemical, X-ray diffraction and X-ray reflectivity approaches, the latter two using bright and collimated light from synchrotron sources; optical tweezers; functional scanning probe microscopies and spectroscopies, grazing angle infrared spectroscopy; and unique applications of X-ray photoelectron spectroscopy. New research facilities, which are used extensively by the department scientists, were completed recently, i.e., the high resolution electron microscopy laboratory, and the combined clean rooms / microfabrication / biological specimen manipulation laboratories. Further facilities are planned, such as a low temperature electrical transport one, in close collaboration with the Chemical Support Services unit.


D. Cahen

MOLECULE-CONTROLLED ELECTRONICS, OPTOELECTRONICS & BIO-OPTOELECTRONICS
D. Cahen, cooperations with M. Sheves, I. Pecht, L. Kronik, C. Sukenik (Bar Ilan), F. Diederich (ETH-Z), A. Kahn (Princeton)

  1.  Molecules as Electronic Conductors: Experiments and Theory to understand the fundamental processes

  2.  Bio-opto-electronics: Understanding the fundamentals by studying electron transport through proteins

SOLAR CELLS. NOVEL ELECTRONIC AND OPTICAL MATERIALS CONCEPTS; BASIC UNDERSTANDING AND MICRO/NANOSCOPIC STUDIES
D. Cahen, cooperation with G. Hodes, S. Cohen, K. Gartsman, I. Lubomirsky; A. Zaban (Bar Ilan U)

  1.  Molecular electronics for solar cells.

  2.  Nano- and poly-crystalline solar cells: how do they work?

  3.  Making optimal use of solar photons


M. Elbaum

Single-molecule manipulations using optical tweezers.

Dynamics of DNA uptake into the cell nucleus.

Structure and function of the nuclear pore complex (with Z. Reich): application of atomic force microscopy and advanced optical spectroscopies.

Anomalous diffusion in polymer networks and living cells (with R. Granek).

Organization of forces driving cell movements (with A. Bershadsky): optical force measurements and particle tracking studies; influence of cell biochemistry on biophysical forces.

Novel surface-patterning lithographies.


G. Hodes

Electrochemical and chemical bath deposition of semiconductor films.

Nanocrystalline solar cells
G. Hodes, D. Cahen

  1.  Semiconductor-sensitized nanoporous cells

Charge transfer in nanocrystalline films


J. Klein

Experimental studies of surface structure and interactions, and of the behavior of confined simple and polymeric fluids.

Surface-forces-measurement techniques at angstrom surface separations; polymers as molecular lubricants; properties of thin liquid films including aqueous electrolytes and polyelectrolytes.

Nuclear reaction analysis investigations of polymer interfaces. Interfacial structure and phase equilibrium between incompatible polymers; studies of transport and self-diffusion in bulk polymers.

Wetting and stability of thin films; use of polymer surfactants to modify surface and interfacial behaviour.


L. Kronik

Unique properties of organic/inorganic interfaces

Theory of novel magnetic materials

Orbital-dependent functionals in density functional theory

real-space computational methodologies


I. Lubomirsky

Properties of Ultra-Thin Self-Supported Crystalline Oxide Films.

Infrared focal plane array based on freestanding pyroelectric films.

Oxygen ion transport in thin freestanding films.


I. Rubinstein

Self-assembled supramolecular systems on surfaces.
I. Rubinstein, A. Vaskevich

Coordination self-assembly of nanostructures comprising organic / inorganic building blocks..
I. Rubinstein, A. Vaskevich, A. Shanzer

Structure, properties and applications of metal island films.
I. Rubinstein, A. Vaskevich

Chemical and biological sensing using localized surface plasmon resonance (LSPR) spectroscopy.
I. Rubinstein, A. Vaskevich

Nanomaterials prepared by template synthesis in nanoporous membranes.
I. Rubinstein, A. Vaskevich


S. Safran

Statistical physics of soft matter and biological physics (theory)

  1.  Single cell physics and cell activity: cell shape, orientation, mechanics and polarization.

  2.  Cooperative physics of cell activity: cell-surface interactions (adhesion), cell-cell elastic interactions.

  3.  Inhomogeneous membranes, physics of inclusions in membranes: connection to lipid rafts.

  4.  Membrane self-assembly of surfactants, lipids, and amphiphilic polymers.

  5.  Electrostatic and fluctuation induced interactions in charged colloidal and membrane systems.

  6.  Coupling of shape and shear elasticity in membranes and in biological cells.


J. Sagiv

Supramolecular Surface Chemistry: Bottom-up Nanofabrication using Planned Self-Assembling Mono- and Multilayer Systems
J. Sagiv, R. Maoz

Constructive Lithography: Contact Electrochemical Surface Patterning on Lateral Length Scales from Nanometer to Centimeter
J. Sagiv, R. Maoz


R. Tenne

Inorganic nanotubes and inorganic fullerene-like materials: new materials with cage structure.


D. Wagner

Interface micromechanics in composite materials, including characterization by micro-Raman spectroscopy.

Mechanics of single- and multi-wall carbon nanotubes, nanofibers and their composites.

Mechanics of biological composites.
D. Wagner, S. Weiner, L. Addadi