Nitrogen-Doped Carbon Quantum Dots-Decorated Mg-Al Layered Double Hydroxide-Supported Gold Nanocatalysts for Efficient Base-Free Oxidation of Benzyl Alcohol

A nitrogen-doped carbon quantum dots (NCDs)-decorated Mg-Al layered double hydroxide (MgAl-LDH)-supported gold nanoparticle (NP) was employed in the aerobic oxidation of benzyl alcohol under solvent-free and base-free conditions. Comprehensive characterizations revealed that the decoration of NCDs improved surface basicity of NCD/MgAl-LDH and was beneficial to the stabilization of gold NPs. Compared with MgAl-LDH-supported gold catalyst, Au/NCD/MgAl-LDH showed much better catalytic activity, along with a turnover frequency of about 20 175 h–1for benzyl alcohol conversion. The promoted catalytic efficiency of the NCD/MgAl-LDH-supported Au catalyst was mainly correlated with unique cooperation between surface hydroxyl arrays at the brucite-like lattice of MgAl-LDH matrix and highly dispersed NCDs, thereby favoring the adsorption and activation of alcohol hydroxyls. Furthermore, compared with Au/MgAl-LDH, Au/NCD/MgAl-LDH showed better structural stability due to the strong Au–NCDs interactions. The primary finding opens a promising approach to develop other highly efficient metal-based catalysts applied in various base-catalyzed heterogeneous reactions.