Australian research: Peanut shells "turn waste into treasure" for preparing graphene

Researchers at the University of New South Wales in Australia have recently developed a method for producing high-quality graphene from waste peanut shells. This opens the door for manufacturing cheaper, more sustainable electronic products and energy storage devices, and helps to reuse agricultural waste. Graphene is composed of a single layer of carbon atoms arranged in a hexagonal lattice, and is one of the thinnest, strongest, and best-conducting materials known to science, earning it the title of "miracle material." The research team explained that peanut shells are rich in lignin, a natural polymer rich in carbon elements. They have developed a new method that involves a series of heat treatment steps to rearrange the carbon atoms in lignin to produce high-quality graphene. The new method involves two steps to produce graphene using peanut shell powder. The first step involves heating to 500 degrees Celsius for 5 minutes to remove impurities and generate carbon-rich material; then the carbon material is subjected to flash joule heating, where the material is rapidly heated to 3000 degrees Celsius in milliseconds using an instantaneous electric current, rearranging the carbon atoms into a single layer of graphene. The researchers emphasized the importance of the first step in removing impurities and providing optimal carbon-rich material to minimize defects in the final graphene product. The researchers noted that traditional graphene production is costly and energy-intensive, but the new method using agricultural waste and no industrial chemicals can significantly reduce costs and carbon emissions. The energy cost for producing 1000 grams of graphene is only $1.3. They plan to commercialize the method within three to four years and test the production of graphene using other waste materials such as coffee grounds and banana peels. The research findings have been published in the international journal "Progress in Chemical Engineering."