Structure-Activity Relationships for Pt-Free Metal Phosphide Hydrogen Evolution Electrocatalysts

Area of Science:

• Renewable energy
• Electrochemistry
• Materials science

Background:

• Water electrolysis is key for renewable hydrogen fuel production.
• Platinum-group catalysts are effective but costly and rare.
• Earth-abundant catalysts are needed for efficient water splitting.

Purpose of the Study:

• Review the use of 3d-transition metal phosphides as catalysts for the hydrogen evolution reaction.
• Discuss the relationship between the electronic and crystal structures of Fe, Co, and Ni phosphides and their catalytic activity.
• Summarize synthetic methods for these advanced electrocatalysts.

Main Methods:

• Analysis of electronic and crystal structures (bulk and surface) of Fe, Co, and Ni phosphides.
• Correlation of structural properties with experimental catalytic activity data.
• Review of various synthetic protocols for transition metal phosphide electrocatalysts.

Main Results:

• 3d-transition metal phosphides exhibit excellent activity and stability for hydrogen evolution.
• Specific electronic and crystal structures are linked to enhanced catalytic performance.
• Diverse synthetic routes enable the production of state-of-the-art phosphide catalysts.

Conclusions:

• Transition metal phosphides are promising, cost-effective alternatives to platinum for water electrolysis.
• Understanding structure-activity relationships is crucial for designing efficient phosphide electrocatalysts.
• Advancements in synthesis are enabling the development of high-performance phosphide catalysts for renewable hydrogen production.