Rational Design of Ruthenium and Cobalt-Based Composites with Rich Metal-Insulator Interfaces for Efficient and...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Hydrogen energy production via water electrolysis is crucial for a sustainable future.
• Developing cost-effective and highly active electrocatalysts for acidic media remains a challenge.
• Proton exchange membrane (PEM) and membrane-free electrolysis require stable bifunctional catalysts.

Purpose of the Study:

• To design and synthesize a novel Ruthenium-modified cobalt-based electrocatalyst.
• To achieve high activity and stability for overall water splitting in strongly acidic environments.
• To explore the potential of Mott-Schottky heterostructures in electrocatalysis.

Main Methods:

• Fabrication of a Ruthenium-modified cobalt-based electrocatalyst embedded in a nitrogen-doped carbon (NC) matrix.
• Utilizing a Mott-Schottky heterostructure with RuO2/Co3O4-RuCo@NC composites.
• Characterization of the electrocatalyst's performance in acidic media for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).

Main Results:

• The RuO2/Co3O4-RuCo@NC composite exhibited remarkable electrocatalytic activity for both OER and HER.
• Achieved low overpotentials of 247 mV for OER and 141 mV for HER.
• Demonstrated excellent stability in 0.5 M H2SO4, comparable to alkaline conditions, with a cell voltage of 1.66 V for overall water splitting at 10 mA cm-2.

Conclusions:

• The developed Mott-Schottky heterostructure catalyst offers a new pathway for designing efficient bifunctional electrocatalysts.
• The catalyst's stability in acidic media is attributed to a protective carbon thin film.
• This work advances the field of electrocatalysis for acidic water electrolysis and hydrogen production.