More recent studies of alcohol oxidation in the liquid phase tend to focus on supported nanoparticles of metals such as Au, Pd, and Pt, highly active and selective with respect to their non-noble counterparts. Generally, gas-phase reactions are characterized by higher turnover frequencies, while apparent activation energies are considerably lower in the liquid phase. This effect is attributed to the promotional activity of solvents, especially water, which enhances substrate adsorption and O2 activation. The rate-determining step (RDS) is widely acknowledged to be the activation of the C-H bond on the α-carbon. The stability of supported metal catalysts is a critical drawback of such catalysts, especially in terms of sintering of nanoparticles and leaching due to the chelating effect of the reaction species. More resilient towards leaching is the class of oxide catalysts, which are bulk materials. On the other hand, the surface of such catalysts is generally ill-defined, presenting a challenge in identifying active sites and understanding reaction mechanisms. Nevertheless, the use of oxides allows great freedom for what concerns the modulation of the surface properties by modifications such as changing the distribution of cations and their overall oxidation degree, or the oxide phase altogether, tuning the active sites.