Carbyne, a one-dimensional chain of carbon atoms, is incredibly strong for being so thin, making it an intriguing possibility for use in next-generation electronics, but its extreme instability causing it to bend and snap on itself made it nearly impossible to produce at all, let alone produce enough of it for advanced studies. Now, an international team of researchers, including from Penn State, may have a solution.
The research team has enclosed carbyne in single-walled carbon nanotubes - tiny, tube-shaped structures made entirely of carbon that are thousands of times thinner than a human hair. Doing this at low temperatures makes carbyne more stable and easier to produce, potentially leading to new advancements in materials science and technology, the researchers said. They called the development "promising news," as scientists have struggled for decades to create a stable form of carbyne in large enough quantities for deeper investigation.
"The history of carbyne's discovery is like a detective story," said Slava V. Rotkin, professor of engineering science and mechanics and co-author of the study published ACS Nano. "It was predicted theoretically, but for many years, attempts to synthesize it were unsuccessful because the chains would either bend or form unintended bonds."
This instability made it difficult to study and even harder to imagine using in real-world applications. However, like graphene, the atomically thin two-dimensional carbon material already applied in some electronics, carbyne's extreme strength and electronic properties continued to entice researchers with its potential to revolutionize electronics, Rotkin said. The pull is even greater with carbyne, though, as it has a built-in advantage over graphene.
"Like graphene, carbyne can allow electrons to move very quickly," Rotkin said. "However, carbyne also has something called a 'semiconductor gap,' which makes it useful for building transistors, the tiny switches that power electronics. Graphene, on the other hand, doesn't have this gap, so it can't be used in the same way."
A semiconductor gap is a small energy gap that allows a material to act as a switch for electrical current. Graphene, in its pure form, cannot be a transistor in of itself because electrons can always flow through it since it doesn't have this gap. Graphene can be engineered to have a gap through various additions and manipulations, but carbyne has the gap naturally. This means that in the future, carbyne-based electronics could more easily offer faster, more efficient performance compared to today's silicon-based technology.
