Surface-Modified Ruthenium Nanorods for an Ampere-Level Bifunctional Hydrogen Evolution Reaction/Oxygen Evolution...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Bifunctional ruthenium electrocatalysts face limitations due to inactive facets on nanoparticles.
• Ruthenium nanorods offer potential for enhanced electrocatalysis due to dominant active facets, but their synthesis is challenging.
• Catalyst surface properties significantly influence the adsorption capacity of reaction intermediates.

Purpose of the Study:

• To synthesize surface-modified ruthenium nanorods with a dominant active facet (hcp (100)).
• To investigate the electrocatalytic performance of these modified nanorods for hydrogen and oxygen evolution reactions.
• To confirm the role of surface modification in optimizing catalytic activity via theoretical studies.

Main Methods:

• Surfactant coordination method for synthesizing surface-modified ruthenium nanorods (SMRu-NRs@NF).
• Electrochemical testing in acidic and alkaline solutions for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER).
• Density functional theory (DFT) calculations to analyze reaction energy barriers.

Main Results:

• SMRu-NRs@NF demonstrated ultralow overpotentials for HER (215 mV in acid, 185 mV in alkaline) at 1000 mA cm⁻².
• Excellent OER performance was observed in alkaline solution with a low potential of 1.58 V at 1000 mA cm⁻².
• High durability exceeding 143 hours was achieved for both HER and OER at 1000 mA cm⁻².
• DFT studies confirmed that surface modification optimizes reaction energy barriers for intermediates.

Conclusions:

• Surface-modified ruthenium nanorods with chemisorbed oxygen and OH groups provide a viable strategy for efficient electrocatalysis.
• This approach enables the development of practical and durable electrocatalysts for water splitting.
• The study paves the way for advanced catalyst design by controlling surface properties.