3D graphene created from ‘blown sugar’ technique

Xuebin Wang and Yoshio Bando, of Japan's International Centre for Materials Nanoarchitectonics, used bubbles blown in a polymeric glucose solution to create the structures, which they claim offer excellent conductivity. The researchers began by creating a syrup of ordinary sugar and ammonium chloride. They heated the syrup to generate a glucose-based polymer called melanoidin, which was then blown into bubbles using gases released by the ammonium. The team found they got the best results by using an equal amount of ammonium decomposition and glucose polymerisation. As the bubbles grew, the remaining syrup drained out of the bubble walls, leaving thin intersections of three bubbles. Under further heating, deoxidisation and dehydrogenation, the melanoidin gradually graphitised to form 'strutted graphene': a coherent 3D structure made up of graphene membranes linked by graphene strut frameworks, which resulted from original bubble walls and intersectional skeletons, respectively. According to Bando, the bubble structure allows free movement of electrons throughout the network, meaning that the graphene retains full conductivity even when compressed to 80% of its original size. What's more, the researchers say the method is extremely cheap (the graphene structures were created at a cost of $0.5 per gram) and highly scalable.