New Materials



New Materials

Researchers throughout Berkeley Lab are developing new materials for use in the broadest imaginable range of industrial applications, as well as everyday applications from building materials to biomedicine. A new and growing area of research at Berkeley Lab focuses on nanotechnology.

The examples of energy-efficient new materials that follow were developed or studied at Berkeley Lab.

A sample of GFP baffle, taken out of its barrier bag.

Gas-Filled Panels

Gas-Filled Panels, or GFPs, use thin polymer films and low-conductivity gas to create a device with extraordinary thermal insulation properties. GFPs are essentially hermetic plastic bags that can take on a variety of shapes and sizes. Inside the outer barrier is a cellular structure called a baffle. Argon gas filling provides an effective thermal resistance level of R-7 per inch, krypton gas provides R-12.5 per inch, and xenon gas provides R-20 per inch.

  • Energy use of domestic refrigerator/freezers is directly influenced by the overall thermal performance of the cabinet and doors. An advanced thermal insulation technology can improve the efficiency of appliances such as refrigerators.
  • Insulation materials are critical in buildings designed for low energy use and good thermal comfort. Increasing the thermal resistance, or R-value, of the insulation is an effective strategy to lower heating costs when thermal loads are dominated by the building envelope.
  • Thermal insulation will be increasingly important in the future development of cars because significant improvements in gas mileage can be achieved by downsizing the heating, ventilation, and air conditioning equipment.
  • Waste reduction and higher thermal performance compared to close-cell foam is possible using Gas-Filled Panels. The panels feature low mass and low volume.

Aerogels

Aerogel is a lightweight, advanced material that consists of more than 96 percent air. The remaining four percent is a matrix of silica (silicon dioxide), a principal raw material for glass. This material is one of the lightest weight solids ever developed.

Possible uses include:

  • Environmentally friendly, energy-efficient, recyclable alternatives for polyurethane foam in freezers, refrigerators, refrigerated vehicles and freezer display cases.
  • Alternative insulators in appliances such as water heaters and ovens.
  • Aircraft and aerospace industry applications.
  • Luminescent composites with potential opto-electronic applications.
  • Magnetic composites that may be useful for paramagnetic cooling at ambient temperatures.
  • High surface area carbon monoliths for electrochemical applications.
Hibiscis flower lying on a piece of aerogel that is above a flame.
Light emitting diodes made of indium gallium nitride held clues to the potential new solar cell material.

New Solar Cells

Researchers in Berkeley Lab's Materials Sciences Division (MSD), working with crystal-growing teams at Cornell University and Japan's Ritsumeikan University, have learned that the band gap of the semiconductor indium nitride is not 2 electron volts (eV) as previously thought, but instead is a much lower 0.7 eV.

The serendipitous discovery means that a single system of alloys incorporating indium, gallium, and nitrogen can convert virtually the full spectrum of sunlight-from the near infrared to the far ultraviolet-to electrical current. If solar cells can be made with this alloy, they promise to be rugged, relatively inexpensive-and the most efficient ever created.

Better Fuel Cells

Berkeley Lab researchers have developed a solid oxide fuel cell (SOFC) that promises to generate electricity as cheaply as the most efficient gas turbine.

Their innovation, which paves the way for pollution-free power generators that serve neighborhoods and industrial sites, lies in replacing ceramic electrodes with stainless-steel-supported electrodes that are stronger, easier to manufacture, and, most importantly, cheaper. This latter advantage marks a turning point in the push to develop commercially viable fuel cells.

Stages in the making of a cheaper fuel cell. 1) Tri-layer composed of yttria-stabilized zirconia (YSZ) electrolyte, nickel-YSZ electrode, 
		porous high-strength commercial alloy or metal-ceramic support. 2) fired tri-layer. 3) low-cost, high performance solid oxide fuel cell.
Top view of indirect exciton photoluminescence intensity under laser excitation perpendicular to the planes of the wells.  
		The laser is focused at the bright white spot, leading to a high density of excitons there.  Excitons, which are free to move in the plane of the wells, diffuse away 
		from this area.  Surprisingly, at a temperature of 1.8 K, they form a 400 mm diameter ring with local periodic ordering as revealed by the ring of bright spots.

The Molecular Foundry

The Molecular Foundry at Berkeley Lab will open its doors on a limited scale in late 2003 as an international user facility for the study of the theory, synthesis, and characterization of nanoscale materials. Full scale operations are expected to begin in 2006 when construction of its new laboratory building is complete.

The focus of the Foundry will be on the development and understanding of both "soft" (biological and polymer) and "hard" (inorganic and microfabricated) nanostructured building blocks and their integration into complex functional assemblies. This will be achieved through collaborations with users from around the world in the disciplines of materials science, physics, chemistry, and biological sciences.

Nanowire Nanolasers

One of the smallest lasers ever made-far too small to be seen even with the aid of the most powerful optical microscope-has been successfully tested by a team of researchers with Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley. This device, which emits flashes of ultraviolet light, is called a "nanowire nanolaser" and it measures just under 100 nanometers in diameter or about one ten-millionth of an inch.

Research and Technology Transfer Links

Under an electron microscope, the arrays of nanowire nanolasers look like bristles of a brush, each bristle an individual laser 
		about one thousandth the diameter of a human hair. Photo by Peidong Yang/UC Berkeley, courtesy of Science

Photo by Peidong Yang/UC Berkeley, courtesy of Science

 참조 : http://industrial-innov.lbl.gov/II-materials.html