SYDNEY, Feb 25 — Researchers in Australia have developed a cheaper, greener way to turn discarded peanut shells into graphene, a valuable component for electronics and energy devices, Xinhua reported.
The development opens the door to cheaper, more sustainable electronics and energy storage while transforming peanut shells into graphene — the thinnest, strongest, and most conductive material known — for batteries, solar panels, touch screens, flexible electronics, and super-fast transistors, said a statement from Australia’s University of New South Wales (UNSW) on Wednesday.
The research team found that lignin, a naturally occurring polymer in plants that contains lots of carbon, allows peanut shells to be converted into high-quality graphene through a rapid heating process, it said.
The two-step method involves heating the shells to around 500 degrees Celsius to create a carbon-rich char, then applying flash joule heating of around 3,000 degrees for milliseconds, which rearranges carbon atoms into single-layer graphene without using chemicals or fossil-fuel-based additives, said the study published in the Chemical Engineering Journal Advances.
Researchers said their calculations indicate that a kilogram of graphene can be produced using their method at a cost of just US$1.30 in energy, while cutting both emissions and production time to about 10 minutes.
The researchers plan to explore other organic wastes, such as coffee grounds or banana peels, to be used for large-scale, sustainable, commercial graphene manufacturing within three to four years.
“We’ve used peanuts as a test case, but the key ingredient to this process is the lignin, which is present in many different plants,” said study lead author Guan Yeoh from UNSW’s School of Mechanical and Manufacturing Engineering. — Bernama-Xinhua
