Recent years have seen significant advances in the properties achieved by both these materials, and so researchers have begun to blend these materials into nanocomposites that access the properties of both materials.
The heated probe of an atomic force microscope melts a nanoparticle-polymer composite enabling it to flow onto a surface. The nanocomposite can be used as-is or the nanoparticles released with an oxygen plasma. (Image courtesy of UIUC and NRL.) Forming these nanocomposites into structures has been tricky since each nanocomposite would require a particular set of solvents or a particular surface coating.
To solve this problem, the NRL and UIUC team developed a generic means for depositing many nanocomposites on multiple surfaces with nanoscale precision. Metal nanoparticles that were conducting, tiny magnetic nanoparticles, and nanoparticles that glowed, were all deposited using this one technique.
The technique builds on previous work using atomic force microscopy (AFM) probes as pens to produce nanometer-scale patterns. The polymer-nanocomposite blend is coated onto the probe. When the probe is heated, it acts like a miniature soldering iron to deposit the nanocomposite. "This technique greatly simplifies nanocomposite deposition," said Paul E. Sheehan, head of the Surface Nanoscience and Sensor Technology Section at NRL in Washington, D.C. "No longer do you have to spend half a year tweaking the chemistry of the surface or nanocomposite to achieve deposition."
The technique also solves a common problem when depositing soft materials like polymers and nanocomposites. The solvents and patterning procedures for depositing soft materials can damage any soft material already deposited. Consequently, it can be quite difficult to deposit many different such materials. "Our ability to control nanometer-scale heat sources allows local thermal processing of these nanocomposites," says William King, Kritzer Faculty Scholar in the Department of Mechanical Science and Engineering at the University of Illinois Urbana-Champaign. This opens a door to the direct writing of highly complex structures.
Although the nanoparticles were typically dispersed throughout the nanocomposite, the researchers found that by adjusting the nanoparticle chemistry they could force the nanoparticles into alignment. "With the right chemistry, the forces in the polymer will guide the nanoparticles into thin rows." Rows of nanoparticles less than 10 nm wide were written, narrower than any other direct write technique. The string of magnetic nanoparticles should be useful for studying magnetic interactions on the smallest scales. "Combining with our nanolithographic technique these tiny magnetic nanostructures can be added to current electronic or MEMS devices to enhance their capabilities." says Woo Kyung Lee.
"These capabilities and those of the other nanocomposites may find novel applications from microelectronics to biomedical devices."
The technique was published on January 13th, 2010, in the journal Nano Letters. The research was sponsored by the Defense Advanced Research Projects Agency (DARPA).
Donna McKinney | EurekAlert!
From ancient fossils to future cars
21.10.2016 | University of California - Riverside
Study explains strength gap between graphene, carbon fiber
20.10.2016 | Rice University
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
25.10.2016 | Earth Sciences
25.10.2016 | Power and Electrical Engineering
25.10.2016 | Process Engineering