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 (superconductors and semiconductors); nanomaterials, like carbon nanotubes, and inorganic nanotubes; ultra thin ferroelectric 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; metals and polymers, including polymer brushes and polymers for cloud seeding; and nanocomposites displaying unique mechanical properties. Biopolymer mechanics and molecular transport phenomena in the cell; imitation of biological transport strategies. Planned self-assembly of novel nanostructures on scanning-probe-patterned organic monolayer templates. Three new research groups have been established over the last few years: Dr. Ernesto Joselvich-carbon nanotubes and scanning probe microscopy; Dr. Roy Bar-Ziv-studies the mechanisms of biological transcription on silicon chip using microfabriction and microfluidics. Dr. Leeor Kronik- uses density functional theory to study clusters; magnetic nanoparticles; nanocrystalline material; inorganic-organic interfaces and optical phenomena in semiconductors. The group of Dr. Igor Lubomirsy studies nanocrystalline electrocermaic films, and quasi amorphous films of ceramic materials, in particular.
Several groups in the department are developing novel theoretical and experimental methodologies for probing liquid-liquid, solid-liquid, solid-solid, solid-gas and liquid-gas interfaces. These include force measurements techniques at Ångstrom surface separation; nanomechanical testing of carbon and inorganic nanotubes; electrochemistry; grazing angle X-ray diffraction and X-ray reflectivity using bright and collimated light from synchrotron sources; optical tweezers; scanning probe microscopy and spectroscopy, grazing angle infrared spectroscopy; and unique applications of X-ray photoelectron spectroscopy. Two new research facilities, which are used extensively by the department scientists, have been completed this year, i.e the high resolution electron microscopy laboratory, and the combined clean rooms/microfabrication/biological specimen manipulation laboratory.


D. Cahen 

POLY- & NANO-CRYSTALLINE SOLAR CELLS, THEIR CHEMISTRY & PHYSICS
D. Cahen, in cooperation with G. Hodes, S. Cohen, K. Gartsman; A. Zaban (Bar Ilan U)

  1.  Molecular electronics for poly- and nano-crystalline solar cells.

  2.  Nanocrystalline solar cells: how do they work?

  3.  Self-assembling solar cells (with Univ. Uppsala)

  4.  Scanning probe & Electron beam microscopies for nanoscale solar cell characterization

  5.  How can polycrystalline solar cells outperform than their single crystal analogues?

MOLECULE-CONTROLLED ELECTRONICS, OPTOELECTRONICS & BIO-OPTOELECTRONICS
D. Cahen, Cooperations with M. Sheves, M.vanderBoom, A Shanzer, R.Arad-Yellin,; C.Sukenik(Bar Ilan), F.Diederich(ETHZ), A.Kahn,J.Schwartz(Princeton),G.Meyer(John Hopkins)

  1.  Understanding and controlling electrical contacts to molecules

  2.  Molecular electronic sensors, Fundamentals (why?) and practice (how?)

  3.  Unique molecular electronic device effects: Negative Differential Resistance and more

  4.  Towards bio-optoelectronics:Science and practice of Bacteriorhodopsin- based devices

PHOTO-ASSISTED WATER PURIFICATION: Use of mesoporous, nanoparticulate membrane electrodes.
D. Cahen, in cooperation with A. Zaban (Bar Ilan U), A. Abed Rabbo & H. Hallak (Bethlehem U)

ELECTRON TRANSPORT ACROSS MOLECULES AND MOLECULAR LAYERS
D. Cahen, in cooperation with L. Kronik, A. Nitzan (Tel Aviv Univ.), R. Naaman

  1.  Fundamental mechanisms for electronic charge transport through molecules

  2.  How can information be transferred across insulating molecular layers?


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 

Spintronic materials: electronic and magnetic properties

Organic semiconductors: structural and electronic properties
L. Kronik, E. Umbach, C. Heske (U. Wurzburg, Germany)

Quantum dots: optical properties

Site-specific photoelectron spectroscopy: predicting & explaining experiment
L. Kronik, J. C. Woicik (NIST, USA)

Nano-clusters: non-equilibrium effects

molecular electronics
L. Kronik, D. Cahen (WIS), A. Nitzan (Tel Aviv Univ.)


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 transmission localized surface plasmon resonance (T-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 biomaterials (theory)

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