A research group at Tokyo Institute of Technology has developed an oxidation reaction of hydrocarbons catalyzed by ultrafine nanoparticles "sub-nanoparticles" with a particle size of about 1 nanometer.The hydrocarbon targeted in this study is an organic molecule called toluene, which has an inactive carbon-hydrogen bond, and shows almost no activity with commercially available metal-supported catalysts. The catalytic activity was about 50 times higher than that of known nanoparticles.
The oxidation reaction that converts hydrocarbons, which are the main components of fossil raw materials such as petroleum and natural gas, into useful organic oxides is an important catalytic reaction both academically and industrially.In general, it is known that the catalytic activity is improved by reducing the size of the particles to nano size, and it has been expected that "sub-nanoparticles" having a particularly small size exhibit extremely high catalytic activity.However, it is technically difficult to synthesize particles with extremely small and uniform sizes, and there have been no studies that accurately evaluated the catalytic activity.
In this research, we succeeded in synthesizing sub-nanoparticles with uniform particle size by using a special polymer called dendrimer, which has a dendritic ordered structure, as a template.When a toluene oxidation reaction was carried out using various sub-nanoparticles as a catalyst by this method, it was discovered that the catalytic activity improves as the size of the particles decreases.We also found that platinum, which has a particularly low oxygen affinity among transition metals, exhibits high catalytic activity, and recorded a catalytic activity about 19 times higher than that of known metal nanoparticles in a platinum sub-nanoparticle catalyst with 50 atoms. ..
It is expected that this result will realize high-efficiency production of inert hydrocarbons into industrially useful substances, and will further evaluate the excellent catalytic function hidden in sub-nanoparticles in the future.
This paper was selected as "Very Important Paper (VIP) -Top 5% of all papers-" by the German chemistry magazine "Angewandte Chemie International Edition".
