Ultralow-Overpotential Acidic Oxygen Evolution Reaction Over Bismuth Telluride-Carbon Nanotube Heterostructure with...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Iridium and ruthenium oxides are state-of-the-art for acidic oxygen evolution reaction (OER) but are expensive.
• Economically feasible catalysts require low overpotential, high stability, and resistance to dissolution in acidic OER.

Purpose of the Study:

• To design and evaluate an organometallic core-shell heterostructure as an efficient catalyst for acidic OER.
• To investigate the material composition-structure relationship for enhanced catalytic activity.

Main Methods:

• Synthesis of an organometallic core-shell heterostructure with a carbon nanotube (CNT) core and bismuth telluride (Bi2Te3) shell (nC-Bi2Te3).
• Electrochemical characterization of the nC-Bi2Te3 catalyst for acidic OER performance.

Main Results:

• The nC-Bi2Te3 catalyst achieved an ultralow overpotential of 160 mV at 10 mA cm⁻².
• Demonstrated excellent electrocatalytic activity with a low Tafel slope (30 mV dec⁻¹) and charge transfer resistance (1.5 Ω).
• The catalyst's composition and morphology facilitated hydroxyl group generation, enhancing H⁺ absorption and intrinsic activity.

Conclusions:

• The nC-Bi2Te3 catalyst outperforms precious-metal-based catalysts in acidic OER.
• The study provides insights into material composition-structure relationships for high-performance catalysts.
• This organometallic heterostructure offers a promising, economically feasible alternative for water-splitting technologies.