Scientists at the Department of Energy’s Argonne National Laboratory have invented a molecular-level, stencil-like method for creating futuristic self-assembling materials. The new method enables precise control not only of the chemical composition of a new material, but also of the geometric arrangement of its molecules. Researchers anticipate that this could lead to the development of new kinds of low cost, high efficiency solar cells.
Block Copolymers and Self-Assembling Materials
The new method rests on the unique characteristics of molecules called block copolymers. These complex molecules consist of distinct units that may have opposite characteristics; Argonne writer Jared Sagoff provides the example of a block copolymer in which one unit repels water while the other attracts it. Think of one of those magnetic building toys, and you can see how a thin film of these molecules could result in an organized matrix. If new molecules are laid over this film, the characteristics of each “block” in the matrix will affect how the new layer organizes itself.
Self-Assembling Materials and Solar Energy
The Argonne researchers use a thin film of block copolymers to act as a stencil or template on which to “grow” a new material with the desired characteristics, including molecular-level shapes such as spheres and cylinders. Two of the lead scientists have focused on developing new solar cells that consist of both organic and inorganic elements, and they anticipate that the new method, called sequential infiltration synthesis (SIS), will push their research forward even beyond the “solar tattoo” and other low cost, paint-like emerging solar cell technologies.
Image: “Protection” stencil by Jaymis on flickr.com.
Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. You can also follow her on Twitter @TinaMCasey and Google+.