Encapsulated bacteria-supported palladium nanoparticles in sol–gel material as core–shell catalyst for Mizoroki–Heck reaction.

In modern chemistry, palladium nanoparticles supported on various supports occupy leading positions among catalysts of organic synthesis. Catalysts based on palladium are widely used in various technological processes due to their high activity and stability. Traditionally, silica and alumina, as well as carbon in various modifications, are used as supports. These materials show stability, inertness and a high surface area as metal nanoparticle supports. However, modern research is aimed at finding alternative supports and ways to improve the characteristics of catalysts. In recent years, special attention has been paid to so-called "living" supports, which are represented by plants and microorganisms. This approach is not only environmentally friendly but also opens up new horizons for the preparation of highly efficient catalytic systems.

In the present work, a method for the synthesis of a core–shell palladium catalyst using microbial cells and sol–gel technology was revealed. The core component comprises the bacterial cells of Paracoccus Yeei with distributed palladium nanoparticles on them. The shell component is an organosilicon matrix that ensures the stability of the structure. The conducted studies showed that bacterial cells are completely covered with organosilicate material, while the formation of the outer shell does not have a significant impact on the size and distribution of palladium nanoparticles. It is important to note that the resulting catalyst demonstrates high activity and selectivity in the Mizoroki–Heck reaction, which opens up broad prospects for its practical application in organic synthesis. The developed catalyst can be scaled up and can became the basis for creating a new family of biohybrid catalysts.