PI.086 The role of Iron and Manganese Single Atoms on Crystalline Carbon Nitrides for Selective Photocatalytic C-H Oxidation

Resumo

Single atom catalysis is a field of paramount importance in contemporary science due to its exceptional ability to combine the domains of homogeneous and heterogeneous catalysis. Iron and manganese metalloenzymes, with metal-oxo species as catalytic active sites, have been shown to be effective in C–H oxidation reactions in nature, inspiring scientists to mimic their active sites in synthetic catalytic systems. Herein, a simple and versatile cation exchange method was successfully employed to stabilize low-cost iron and manganese single atoms in poly(heptazine imides) (PHI). The resulting materials were in turn employed as photocatalysts for toluene oxidation, demonstrating remarkable selectivity towards benzaldehyde. The protocol was then extended to the selective oxidation of different substrates, including alkyl aromatics, benzyl alcohols and sulfides. Detailed mechanism investigations revealed that iron- and manganese-containing photocatalysts work similarly via the formation of high-valent M=O species.