Synergistic effects of Bi2O3 and Ta2O5 for efficient electrochemical production of H2O2

Electrochemical oxygen reduction reaction (ORR) through a two-electron pathway has been provided a green route for on-site hydrogen peroxide (H2O2) production. Developing high-selective electrocatalysts for H2O2 production are urgently sought. Herein, a m-Bi2O3/Ta2O5 electrocatalyst (m: Bi mass contents) has been successfully synthesized by simple physical mixing associated with an outstanding selectivity towards H2O2 (94.7%), over 10% higher than Ta2O5 (80.9%) and Bi2O3 (81.7%). 10-Bi2O3/Ta2O5 also exhibits 471 mmol/(gcat center dot h) H2O2 yield with 91.8% Faraday Efficiency. The in-situ generated H2O2 can function as disinfection agent for efficiently deactivating model bacteria (e.g., Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli) within 30 min. In-situ Raman and DFT proposed the synergistic effects of Bi2O3 and Ta2O5 in boosting 2e(-) ORR performance. In this work, it not only presents a high-selective electrocatalyst for 2e(-) ORR, but also provides a new idea for electrocatalyst design from the perspective of reaction process.

Automated summary

A m-Bi2O3/Ta2O5 electrocatalyst with high selectivity towards H2O2 has been successfully synthesized, exhibiting an outstanding selectivity of 94.7% compared to Ta2O5 (80.9%) and Bi2O3 (81.7%). The electrocatalyst also shows high H2O2 yield and Faraday Efficiency, and can efficiently deactivate bacteria. This study presents a high-selective electrocatalyst for the two-electron pathway of oxygen reduction reaction and provides a new perspective for electrocatalyst design.