Ultrasmall particles in the catalysis

Synthesis, stabilization, and applications in the catalytic processes of ultrasmall particles (UPs, from subnanometer up to 10 nm size) and their composites are reviewed. The UPs-driven processes of carbon monoxide, methanol and glycose oxidation, electro-oxidation and electrochemical conversion reactions, decomposition and reduction of organic and inorganic compounds, water splitting, catalysis in fuel cells, CO insertion, C-C coupling, hydrogenation, and cyclization reactions are discussed. Special attention is paid to the preparation techniques of UPs with different sizes by varying reaction conditions and dependence of catalytic process yields or temperature on the UPs size, supporting media, and surface characteristics.