Researchers from Australia's James Cook University and Flinders University recently announced they successfully used cheap agricultural byproduct, nanocellulose, to make graphene - using only water, rather than harsh chemicals.
The team took cellulose derived from woody biomass, converted it to biochar, then used a newly patented vortex fluidic device (VFD) to produce high quality graphene, explained the paper’s first author and JCU PhD candidate Yu Matsueda. “The VFD rotates at very high speed, allowing us to really control the way fluids move inside the device … thus we can control the layers of graphene formed from the initial biochar,” he said “In our research we used water as a solvent, which is more sustainable than current methods.”
The synthesis of graphene was done under slow pyrolysis (500–800 °C) using wood-derived nanocellulose as the starting material. To the authors knowledge, this is the first study to investigate the production of biochar-derived graphene under mild pyrolysis conditions (<900 °C) without the use of external chemicals or catalysts. The nanocellulose crystal (NCC)-derived biochar was characterized, and the material was dispersed in water and processed in the VFD to obtain graphene.
The biochar properties (SSA, morphology, and functional groups) were shown to greatly impact the transformation of the biochar followed by exfoliation, with the VFD conditions optimized to maximize graphene production. This approach shows great promise to be a low-cost, sustainable, and catalyst-free method to synthesize graphene using a lignocellulosic biomass-derived feedstock.
“The graphene we produced was, in fact, very similar to what other people are obtaining from non-renewable resources”, Matsueda said.
The team stated that being able to produce graphene from a renewable resource, like sugarcane fiber, can be an example for other industries trying to create a circular economy.
