Enzyme is the most important ingredient during the formation of lives on the Earth with no doubt. They act as accelerators during the reactions which are of great significance for living beings. It is a nice idea to get inspirations from the nature and design new catalysts by imitating enzymes, which is a hopeful way to get catalysts of high efficiency and low cost.
The group led by Prof. WU Yuen from University of Science and Technology of China (USTC) have developed a biomimetic material called yolk-shell Pd1@Fe1, which has been proved to be able to catalyze reduction and oxidation reactions at the same time. Related works were published on Nature Catalysis.
The researchers designed and prepared samples of unique special distribution, namely, Pd single atoms in the yolk and Fe single atoms in the shell, imitating the structure of enzyme.
After characterizing with different methods, they confirmed the as-prepared samples have the desired appearance and conducted experiments in which amino alcohols being the target product and the sample being the only catalyst involved. Results showed that this novel structure catalyst have high yield as well as selectivity, which are the ultimate pursues for catalysts designing.
The way this yolk-shell Pd1@Fe1 works is interesting and inspiring. Due to the yolk-shell structure, Pd atoms are separated form the initial reactants, which prevents some of the side reactions to take place.
After Fe atoms finish their work (mostly oxidation reactions), the initial reactants have partially transferred to different ingredients, then the processed reactants get in touch with Pd atoms to operate reduction reaction in a row. With some transformation afterwards, amino alcohols are produced with pretty low cost and waste.
This designing method is more than provoking for catalysts designing for its sophisticated usage of spatial distribution. Hopefully this method can inspire many catalysts of high quality to emerge in every field of catalyzing science.

Schema of the newly designed catalyst (Image plotted by Nature Catalysis)
Paper link:
https://doi.org/10.1038/s41929-020-00563-0
(Written by LIU Zige, edited by JIANG Pengcen, USTC News Center)