Green synthesis of a novel porous gold-curcumin nanocomposite for super-efficient alcohol oxidation

Gold nanoparticles (AuNPs) possess tunable size-and shape-dependent properties that are ideal for catalytic properties for many applications. However, the challenge lies in the synthesis of highly stable and ultra-small NPs. We report an energy-efficient galvanostatic route to engineer gold-curcumin (Au-CM) nanocomposites constituting small-sized (-2 nm) AuNPs enveloped by a porous network of curcumin. During electrolytic deposition, the in situ formed Au-CM complexes are the key for the low current involved in our electrosynthesis, which ultimately deposits as CM-enveloped AuNPs at the cathode (Au-CM/GCE). The DFT study also presented high binding energy (18.76 eV) of Au-CM complex in the solvent phase. The Au-CM/GCE nanocomposite exhibited excellent stability (-200 cycles), facile electron transfer ability, catalytic activity, and low Arrhenius energy of 42 and 45 kJ mol(-1), respectively, towards electrooxidation of EtOH and MeOH in alkaline medium. The oxidation kinetics are comparable to those of the best gold-polymer composites. This study points the way for one-pot green synthesis of other engineered electrocatalysts for different applications.

Automated summary

This study reports an energy-efficient galvanostatic route for synthesizing highly stable gold nanoparticles-curcumin nanocomposites. The nanocomposites exhibit excellent stability, catalytic activity, and electrooxidation performance in an alkaline medium.