Molecular Hydrogen Production from Formic Acid by Cationic Phenanthroline Ruthenium Complexes: Experimental and DFT...

Area of Science:

• Organometallic Chemistry
• Catalysis
• Sustainable Energy

Background:

• Ruthenium complexes are vital catalysts in chemical transformations.
• Efficient hydrogen production is crucial for sustainable energy solutions.
• Formic acid is a promising hydrogen storage molecule.

Purpose of the Study:

• To synthesize novel monocationic ruthenium complexes with phenanthroline derivatives.
• To investigate their catalytic activity in formic acid dehydrogenation for H2 production.
• To explore their application in CO2 transfer hydrogenation.

Main Methods:

• Synthesis of monometallic and dinuclear ruthenium complexes.
• Characterization using NMR, FTIR, UV-vis spectroscopy, and cyclic voltammetry.
• Catalytic activity assessment and mechanism investigation via DFT calculations.

Main Results:

• High yield synthesis of novel Ru complexes.
• Selective catalytic activity for formic acid dehydrogenation, with dinuclear systems achieving 100% conversion.
• Dinuclear complexes exhibited excellent stability over multiple cycles.
• Mechanism elucidated involving fac-RuHP2 and mer-RuHP2 hydride species.

Conclusions:

• The developed ruthenium complexes, particularly dinuclear ones, are effective precatalysts for H2 production from formic acid.
• These complexes demonstrate high stability and selectivity.
• The study provides mechanistic insights into the catalytic process and potential for CO2 valorization.