The reducing role of hydrogen peroxide on the formation of gold nanostructures in aqueous microdroplets with dissolved tetrachloroaurate ions

TL;DR

This study investigates how hydrogen peroxide influences the formation of gold nanostructures in aqueous microdroplets containing tetrachloroaurate ions, revealing its significant reducing role compared to other proposed mechanisms.

Contribution

It demonstrates that spontaneously produced hydrogen peroxide plays a key role in reducing AuCl4- to form gold nanostructures in microdroplets, offering new insights into the reduction mechanism.

Findings

Hydrogen peroxide is spontaneously generated at microdroplets.

H2O2 significantly contributes to AuCl4- reduction.

The reduction mechanism involves peroxide as an electron donor.

Abstract

A recent article by Lee et al. in Nature Communications has reported an intriguing phenomenon that gold nanostructures, AuNSs, can be spontaneously formed in aqueous microdroplets with dissolved tetrachloroaurate ions. The authors suggested three possible electron donors for the reduction of AuCl4-, including the strong electric field at the microdroplet surface, the hydroxyl ions, and the AuCl4- itself. However, we find that the hydrogen peroxide spontaneously produced at the microdroplets might be also responsible for the AuCl4- reduction.