The chemical industry seeks a highly active, highly stable, and highly acidic solid material to raise productivity in producing chemicals and in generating energy. Michikazu Hara and his colleagues have developed a material that could fulfill that need. The material is amorphous carbon composed of small graphene sheets thinner than 2 nanometers. It has a high density of sulphonic acid groups (-SO₃H) and is easy to produce from abundant and inexpensive natural organic products, such as cellulose, starch, and sugar. The carbon incorporates large amounts of reactants and exhibits remarkable catalytic performance for various reactions.

An earlier paper published in Nature (438, p. 178 [2005]) described how carbon can function as an innovative catalyst for biodiesel production. Here, Hara and his colleagues describe how it can also function as an efficient catalyst in bioethanol production.