Stable acidic H₂O₂ electrosynthesis via in situ Ti-N bridging sites

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Acidic hydrogen peroxide (H2O2) electrosynthesis is crucial for various industrial applications.
• Catalyst instability remains a significant challenge, limiting efficiency and operational lifespan.

Purpose of the Study:

• To develop a novel catalyst for stable and efficient acidic H2O2 electrosynthesis.
• To investigate the mechanism behind catalyst stabilization.

Main Methods:

• Electrochemical synthesis of H2O2 using the MIL-125@Ppy catalyst.
• Spectroscopic analysis (e.g., in situ spectroscopy) to probe reaction intermediates and active sites.
• Long-term stability testing under acidic conditions (pH=1).

Main Results:

• The MIL-125@Ppy catalyst achieved a high H2O2 yield rate of 69.5 mol gcat−1 h−1.
• A high faradaic efficiency of 82.2% was maintained for over 50 hours of operation.
• Spectroscopic data revealed the formation of Ti-N bridge sites that stabilize the *OOH intermediate.

Conclusions:

• The MIL-125@Ppy catalyst offers a promising solution for stable and efficient acidic H2O2 electrosynthesis.
• The identified Ti-N bridge sites are key to the catalyst's enhanced stability and selectivity.
• This work advances the development of robust electrocatalysts for chemical production.