We can't help but feel that Leonardo da Vinci would approve. Using the Mona Lisa as a template, researchers at the Georgia Institute of Technology have demonstrated a new technique for producing confined chemical reactions on a nanoscale level.
Called the "Mini Lisa," the work is the result of a process called ThermoChemical NanoLithography (TCNL). Using an atomic-force microscope -- a fairly common piece of lab equipment -- the team used a cantilevered arm to apply heat to a chemically coated surface, pixel by 125-nanometer pixel.
The heat applied created a chemical reaction, lightening the surface. The more heat that was applied, the lighter the surface grew. By tightly controlling how much heat was applied to each pixel, the team could control how many new molecules were created.
Creating chemical concentration gradients is difficult with other techniques. The benefit of this one is that the equipment isn't hard to come by, and the technique itself is pretty straightforward, opening up possible applications in nanomanufacturing.
"We envision TCNL will be capable of patterning gradients of other physical or chemical properties, such as conductivity of graphene," said the study's lead author, associate physics professor Jane Curtis. "This technique should enable a wide range of previously inaccessible experiments and applications in fields as diverse as nanoelectronics, optoelectronics, and bioengineering."
The team published its findings, "Fabricating Nanoscale Chemical Gradients with ThermoChemical NanoLithography," in the journal Langmuir.
(Source: Crave Australia)