A cost-effective 3D hydrogen evolution cathode with high catalytic activity: FeP nanowire array as the active phase

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Natural [FeFe]-hydrogenases offer high hydrogen evolution activity but are oxygen-sensitive and difficult to scale.
• Abundant and inexpensive transition metals are sought for efficient electrocatalysts.

Purpose of the Study:

• To develop a robust, cost-effective, non-noble metal catalyst for hydrogen evolution reaction (HER).
• To investigate the electrocatalytic performance and durability of iron phosphide (FeP) nanowire arrays for water splitting.

Main Methods:

• Fabrication of FeP nanowire arrays on a titanium plate (FeP NA/Ti) via low-temperature phosphidation of a β-FeOOH NA/Ti precursor.
• Electrochemical characterization of the FeP NA/Ti electrode as a self-supported 3D hydrogen evolution cathode.

Main Results:

• The FeP NA/Ti electrode exhibited exceptional catalytic activity and durability for hydrogen evolution.
• Low overpotentials of 55 and 127 mV were required for current densities of 10 and 100 mA cm⁻², respectively.
• The catalyst demonstrated a high performance-price ratio.

Conclusions:

• FeP nanowire arrays are highly promising non-noble metal electrocatalysts for efficient and scalable hydrogen production via water splitting.
• The developed material offers a viable alternative to precious metal catalysts in electrochemical energy conversion.