Every year many new materials (and variations on older materials) are brought into the world. Some of them are known only to specialists, and slip into obscurity. Some go straight to commercial application. Some few show ‘great promise.’ This means there’s something unproven about the material, but its properties indicate it could be important. Nonacene is one of these, a flexible organic semiconductor with excellent electrical properties – but a history of being unstable and unusable, until now.
Knowing that instability was the weakness of nonacene, the research team looked for ways to add something to the nonacene molecule that would stabilize it. They rebuilt the nonacene molecule (an acene chain of benzene rings) piece by piece. At each iteration, they tried various compounds. Eventually they settled on molecules of the aryl thiol group containing sulfur. Binding this molecule onto the nonacene molecule not only added stability, but made the compound water soluble – a very useful property for processing.
While Miller [University of New Hampshire, USA] notes that his team’s work is but a first step toward creating stable nonacene devices, “these compounds push all of these technologies further.”
“Before our work, the thought of preparing flexible organic electronic devices using nonacene or a nonacene derivative was just a dream,” he adds. “With this major step forward, we are much closer to realizing the dream.”
Nonacenes hold promise for further development of flexible organic electronic devices: computer displays so thin they could be rolled up or even worn. Miller notes that the military is interested in the technology that would allow for chameleon-like camouflage clothing that could change with the environment. Organic solar cells are another potential application of nonacenes; such cells could cut the cost of solar power by making use of inexpensive organic molecules rather than the expensive crystalline silicon that is used in most solar cells.
Not many of the hyped new materials will become important either commercially or in scientific work. There are always hurdles: Production problems, material cost, maintenance issues, inability to scale (greater numbers)…among other things. Nonacene does not look like it will be one of the washouts, but time will tell. As they say, “Keep an eye on this one.”