Vacancy-Activated B-Doping for Efficient 2e^- Oxygen Reduction through Suppressing H₂O₂ Decomposition at High...

Area of Science:

• Electrochemistry
• Materials Science
• Green Chemistry

Background:

• Traditional anthraquinone methods for hydrogen peroxide (H2O2) production are energy-intensive and environmentally impactful.
• While carbon catalysts show promise for the two-electron oxygen reduction reaction (2e- ORR), H2O2 yield and conversion are limited by decomposition at high potentials.
• Peroxide radical decomposition under high voltage in carbon catalysts hinders efficient H2O2 production.

Purpose of the Study:

• To develop a highly efficient B-doped carbon catalyst for 2e- ORR.
• To suppress H2O2 decomposition at high potentials for improved yield and conversion.
• To establish a green and scalable pathway for H2O2 synthesis.

Main Methods:

• Synthesized B-doped carbon by thermally reducing oxygen-containing groups (OCGs) on graphite.
• Investigated the catalyst's ability to suppress H2O2 decomposition and stabilize intermediates.
• Evaluated the catalyst performance for 2e- ORR at industrial current densities.

Main Results:

• B-doped carbon effectively prevented H2O2 decomposition by stabilizing the *O-O bond and *OOH intermediates.
• Achieved excellent selectivity for 2e- ORR across a wide voltage range.
• Delivered a remarkable H2O2 yield of 7.91 mmol cm-2 h-1 at 600 mA cm-2.

Conclusions:

• B-doped carbon is a highly effective catalyst for efficient 2e- ORR.
• This approach offers a green and scalable pathway for industrial H2O2 synthesis.
• The catalyst's ability to suppress decomposition is key to achieving high H2O2 yields.