Polymerizable Ionic Liquid-Derived N, S co-Doped sp³/sp² Carbon as Electrocatalyst for H₂O₂ Generation

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Green electrochemical hydrogen peroxide (H2O2) generation is crucial.
• The oxygen reduction reaction (ORR) is key for H2O2 synthesis but is kinetically limited.
• Noble metal catalysts for ORR are expensive and impractical for widespread application, necessitating non-precious metal alternatives.

Purpose of the Study:

• To develop and investigate a metal-free catalyst for efficient H2O2 production via the 2-electron oxygen reduction reaction (2e- ORR).
• To explore the use of heteroatom-doped carbon materials with modulated sp2/sp3 hybridization for ORR catalysis.
• To demonstrate a simple synthesis technique for tunable carbon catalysts.

Main Methods:

• Synthesis of nitrogen, sulfur, and cadmium co-doped carbon with modulated sp2/sp3 hybridization using a polymerizable ionic liquid.
• Electrochemical characterization of the synthesized carbon material as a catalyst for the oxygen reduction reaction.
• Evaluation of catalytic activity, onset potential, and selectivity for H2O2 production.

Main Results:

• The synthesized N, S co-doped carbon with sp2/sp3 modulation demonstrated promising ORR catalytic activity.
• An onset potential of 0.88 V vs. RHE was achieved for the 2e- ORR process.
• Approximately 50% selectivity towards H2O2 generation was obtained, highlighting its potential for green synthesis.

Conclusions:

• A facile method for synthesizing heteroatom-doped sp2/sp3 engineered carbon catalysts was developed.
• The study provides a new approach to tune the catalytic activity of carbon materials for electrocatalytic O2 reduction to H2O2.
• The developed metal-free catalyst shows significant potential for sustainable and cost-effective H2O2 production.