Approaches to the synthesis of Pd/C catalysts with controllable activity and selectivity in hydrogenation reactions.

• Controllable activity and selectivity of Pd/C hydrogenation catalysts. • Effect of the carbon support on the structure and catalytic properties of Pd NPs. • Effect of the Pd precursor on the structure and catalytic properties of Pd NPs. • Addition of a second metal and the synergistic effect in Pd-based bimetallic catalysts. Carbon-supported palladium catalysts are widely used for hydrogenation of various organic compounds in the fine chemical industry. The nanoscale geometry and electronic structure of supported Pd nanoparticles play a crucial role in providing the necessary catalytic properties. To improve catalytic activity and selectivity of Pd nanoparticles, it is possible to fine tune their intrinsic properties (e.g., size and oxidation state) by controlling the chemical transformations at different stages of catalyst preparation. Recent years have seen considerable advancement in developing new catalyst preparation techniques as well as in understanding the mechanism of active site formation. This review summarizes some of the existing approaches to regulating the catalytic properties of carbon-supported palladium by variation of the carbon support, the composition of palladium precursor and its reduction conditions, as well as the addition of a second active metal. The data presented may be useful for researchers developing efficient Pd/C catalysts for hydrogenation of polyfunctional organic compounds. [ABSTRACT FROM AUTHOR]