Iridium Catalyst Immobilized on Crosslinked Polyethyleneimine for Continuous Hydrogen Production Using Formic Acid

Area of Science:

• Catalysis
• Sustainable Energy
• Materials Science

Background:

• Hydrogen is a key alternative fuel for achieving net zero emissions and global environmental sustainability.
• Formic acid dehydrogenation (FADH) is a promising route for hydrogen production.

Purpose of the Study:

• To synthesize and characterize a novel iridium-immobilized catalyst for efficient hydrogen production via FADH.
• To evaluate the catalytic activity, stability, and durability of the developed catalyst.

Main Methods:

• Synthesis of an iridium-immobilized catalyst using polyethyleneimine (PEI) and cross-linked iridium complex.
• Characterization of the catalyst structure using solid-state NMR, DNP NMR, and FTIR spectroscopies.
• Testing catalytic performance for FADH, including turnover frequency (TOF) and turnover number (TON) measurements, and continuous hydrogen production over 2,000 hours.

Main Results:

• The iridium-immobilized catalyst demonstrated excellent catalytic activity for FADH.
• Achieved a high TOF of 73,200 h⁻¹ and a TON exceeding 1,130,000.
• Exhibited high durability for continuous hydrogen production over 2,000 hours with a TON of 332,889 without activity loss.
• Successfully generated power using the produced hydrogen in a fuel cell for 5 hours.

Conclusions:

• The PEI-based iridium-immobilized catalyst is highly effective and durable for hydrogen production via FADH.
• This catalyst represents a significant advancement in sustainable hydrogen generation for clean energy applications.
• The developed system shows potential for continuous, stable hydrogen supply for fuel cell applications.