Unraveling the Synergy between Gold Nanoparticles and Chromium-Hydrotalcites in the Aerobic Oxidation of Alcohols

The strong synergy between chromium-hydrotalcite support and gold nanoclusters is unraveled. It is the result of facile oxygen activation on surface Cr³⁺ sites resulting in Cr⁶⁺ species, which facilitate alcohol O-H bond cleavage, followed by rate-limiting C-H bond cleavage on Au. Upon water removal Cr⁶⁺ is reduced back to Cr³⁺.