This gold catalyst takes the crown for high activity and selectivity

Gold catalysts have been shown to have superior activities for oxidation reactions, especially at low temperature, compared to other metal-based catalysts. But the high price of gold makes it necessary to develop Au catalysts with ever-higher activities, reducing the amount of Au needed. A promising step in this direction is a new type of catalyst developed by Professor Naoki Toshima and his research group at the Tokyo University of Science, Yamaguchi (Yamaguchi, Japan; www.ed.yama.tus.ac.jp/toshima), with support from Japans Science and Technology Agency. The catalyst is a nano-cluster of gold and palladium with a crown-jewel (CJ) structure (CJ-Au/Pd NC). The group has developed a very simple procedure for synthesizing the CJ-Au/Pd NC in which reactive Pd atoms at the corners of the nanocluster are replaced by Au atoms. A nanocluster (1.8-nm dia.) with 135 Pd atoms and 12 Au atoms was produced, and the Au atoms arranged at the special positions that result in extremely high catalyst activities. As a test reaction, the researchers studied the oxidation of glucose into gluconic acid — a widely used food additive. The CJ-Au/Pd NC was shown to have an activity 3.8 and 3.1 times higher than existing Pd and Au clusters, and the selectivity…