Ilustration: Gary Cheng/Purdue University
With news just last week that nanodiamonds could aid in the development of new methods for drug delivery and cancer therapeutics, the prospects for successful cancer treatment got a shot in the arm.
While medical applications for nanodiamonds got a boost, it left the fortunes of nanodiamonds in electronics-related applications a bit out in the cold. The wait was not long, however, with research out of Purdue University that demonstrated a pulsed laser could be used to create synthetic nanodiamond films and patterns on the surface of graphite. This development should have an impact on potential applications for nanodiamonds including biosensors, quantum computing, fuel cells and next-generation computer chips.
"The biggest advantage is that you can selectively deposit nanodiamond on rigid surfaces without the high temperatures and pressures normally needed to produce synthetic diamond," said Gary Cheng, an associate professor of industrial engineering at Purdue University, in a press release. "We do this at room temperature and without a high temperature and pressure chamber, so this process could significantly lower the cost of making diamond. In addition, we realize a direct writing technique that could selectively write nanodiamond in designed patterns."
In research published in the Nature journal Scientific Reports, the Purdue team started with a multilayered film containing a layer of graphite and covered with a glass sheet. They then exposed this layered structure to an ultra-fast pulsing laser that instantaneously transformed the graphite into an ionized plasma that generates a downward pressure. The graphite plasma is prevented from escaping by the glass cover of the multilayered film where, trapped, it quickly solidifies into diamond.
"These are super-small diamonds and the coating is super-strong, so it could be used for high-temperature sensors," Cheng said in the release.
Strength was always the aim of the research. In fact, the technique was originally developed to find a way to strengthen metals. It was only serendipitously that they discovered that it produced this nanodiamond film.
With this development, the researchers believe nanodiamonds could begin to have an impact in electronics. For instance, nanodiamonds have been suggested as a way to get quantum computers to operate at room temperature as opposed to near absolute zero. This would be accomplished by replacing the ions used in some quantum computers with nitrogen-vacancy centers in diamonds.
Nanodiamonds could also lead to next-generation computer chips based on optical transitors in which photons replace electrons. In this scenario, nanodiamonds would replace the special dye molecules that are used in today’s optical transistors. The use of these dyes requires special cooling, which eliminates them from practical use. However, researchers at the Institute of Photonics Sciences (ICFO) in Barcelona demonstrated last year showed that nanodiamond operating at room temperature could be used in an ultrafast optical switch, replacing the dye molecules.