Gold Nanoclusters on Anodized Glassy Carbon as an Electrocatalytic Glucose Sensing Platform

This study employs a scalable, environmentally friendly method to synthesize highly active Au nanoclusters on glassy carbon via gas-phase cluster beam deposition, without ligands or toxic chemicals. To assess the effect of electrochemical pretreatment of the support, four monolayer equivalents of Au nanoclusters were deposited on both bare and anodized glassy carbon. Postanodization, the glassy carbon surface was found to be rougher and enriched with oxygen functional groups. Glucose oxidation was used as a model reaction, and after normalizing by the electrochemically active area, anodized electrodes exhibited a sensitivity of 9.13 ± 0.17 μA·cm–2·mM–1, nearly double the sensitivity of 4.9 ± 0.07 μA·cm–2·mM–1 observed for the same cluster loading on bare glassy carbon. This improvement is attributed to synergistic interactions between the clusters and the activated support. These findings demonstrate the feasibility of producing monodisperse gold nanoclusters in a cleanroom-compatible environment and highlight the alkaline anodization of glassy carbon as an effective strategy for enhancing their electrocatalytic activity. This approach advances high-performance electrocatalytic systems for glucose oxidation and beyond.