Researchers are using the ancient art of blown sugar to produce three-dimensional graphene for supercapacitors.

Graphene is a two-dimensional material made from a single layer of carbon atoms. Despite being very thin, graphene is extremely

Image: Professor Ji-Hyun Jang

strong, lightweight, and excellent at conducting electricity, so it has a wide range of potential applications. The ability to make three-dimensional graphene structures would increase its potential further, but this has proved difficult. Most attempts have resulted in structures that have poor electrical conductivity and lack strength, but recent work led by researchers at Japan’s World Premier International Center for Materials and Nanoarchitectonics (WPI-MANA) has overcome these problems for the first time.

The WPI-MANA team used a technique based on the ancient art of blown sugar to produce a structure consisting of a network of conjoined graphene bubbles, similar to the structure of a sponge. The researchers heated a syrup of ordinary sugar to form a structure called melanoidin. This syrup was mixed with ammonium chloride, which produced gas to create bubbles. As the reaction continued, the melanoidin bubble walls gradually formed graphene, finally setting into a solid structure they called “strutted graphene”, made of the original bubble walls and interconnecting struts.

The team showed that strutted graphene is extremely strong and can be compressed to 80% of its size without collapsing. What’s more, it also retains full electrical conductivity. Costing just US$0.5 per gram to produce, this makes it suitable for many applications, including supports, chemical catalysts, hydrogen reservoirs, gas sensors and air filters. The team also showed that strutted graphene can act as a supercapacitor that stores a large amount of electricity, with the potential to create more efficient batteries that charge more quickly, store more power and have a longer lifespan.

 

For further information contact:

International Center for Materials Nanoarchitectonics
World Premier International Research Center Initiative
National Institute for Materials Science, Japan
Email: mana-pr@ml.nims.go.jp