Electrically controlled silver salt oxide particle synthesis on a closed wireless nanopore electrode

Ag6O8·AgHSO4 is a strong oxidizer that can be easily synthesized, but its unstability causes the self-decomposition easily. To effectively control and monitor this unstable process for synthesis, we used a closed wireless nanopore electrode (CWNE) to realize the repeated electrosynthesis and decomposition of Ag6O8·AgHSO4 at the nano interface. The in situ dark field images traced the highly repeatable growth and dissolution of the Ag6O8·AgHSO4 particle. The real-time current recording revealed that the Ag6O8·AgHSO4 particle growth process is synchronized with the electrocatalytic process. The rapid catalytic process of water oxidation causes two-step bubble coverage to block the electrode surface area. The calculated effective electrode area ratio (Φ) of the two stages were 68.9–82.6% and 14.5–25.6%. These results indicated that with the growth of the Ag6O8·AgHSO4 particle, the crystal plane also grew proportionally, which allowed the bubbles to block similarly on this crystal plane during the electrodeposition. Therefore, our results demonstrate that the CWNE can not only electrically control the growth of an unstable single particle with high repeatability, but also directly and in situ characterize gas−liquid−solid catalytic reactions for unstable catalysts.