Crystallinity dependence for high-selectivity electrochemical oxygen reduction to hydrogen peroxide

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Hydrogen peroxide (H2O2) is a vital chemical with widespread industrial applications.
• Efficient and selective electrochemical synthesis of H2O2 from oxygen (O2) is a key challenge in sustainable chemistry.

Purpose of the Study:

• To develop a novel semiconducting metal-organic graphene analog catalyst for efficient electrocatalytic O2 reduction to H2O2.
• To investigate the effect of crystalline structure on catalytic performance.

Main Methods:

• Synthesis of a metal-organic graphene analog, Ni3(HITP)2, with tunable crystallinity.
• Electrochemical characterization including cyclic voltammetry and chronoamperometry.
• Analysis of catalytic selectivity and activity for O2 to H2O2 conversion.

Main Results:

• The as-prepared 5-Ni3(HITP)2 catalyst with low crystallinity demonstrated high selectivity (80%) for H2O2 production.
• Efficient catalysis occurred over a wide potential range (0.2-0.6 V vs. RHE).
• A high mass activity of 292 A gNi-1 was achieved at 0.25 V in 0.1 M KOH.

Conclusions:

• Ni3(HITP)2 serves as an effective electrocatalyst for selective H2O2 synthesis.
• Catalyst crystallinity plays a crucial role in mediating the efficiency of O2 electroreduction.
• This material offers a promising pathway for sustainable H2O2 production.