Probing Oxygen-to-Hydrogen Peroxide Electro-Conversion at Electrocatalysts Derived from Polyaniline

Area of Science:

• Electrochemistry
• Materials Science
• Green Chemistry

Background:

• Hydrogen peroxide (H2O2) is industrially vital but produced via energy-intensive methods.
• Electrosynthesis offers a decentralized, renewable route for H2O2 production.
• Polyaniline-derived materials previously showed promise for H2 production.

Purpose of the Study:

• To investigate polyaniline-based materials for selective H2O2 production.
• To evaluate the electrocatalytic conversion of O2 to H2O2 via a two-electron pathway.
• To assess the impact of nickel and cobalt on material performance.

Main Methods:

• Synthesis of nine polyaniline-based materials with varying nickel and cobalt content.
• Thermal treatment under air and inert gas atmospheres.
• Electrochemical evaluation using rotating ring-disk electrode (RRDE) and electrolysis with spectrophotometry.

Main Results:

• Cobalt species were found to inhibit electrocatalytic performance.
• Selectivity for H2O2 ranged from 65-80% for polyaniline and nickel-modified polyaniline.
• Production rates comparable to state-of-the-art Vulcan XC 72R were achieved with nickel-modified polyaniline.

Conclusions:

• Polyaniline and nickel-modified polyaniline are effective electrocatalysts for H2O2 production.
• These materials offer a promising pathway for decentralized, renewable H2O2 synthesis.
• Further research could optimize these materials for enhanced efficiency and stability.