Covalently linked triarylborane-iridium(III) complex as a photocatalyst for CO₂ reduction

Area of Science:

• Organometallic Chemistry
• Photocatalysis
• Carbon Dioxide Reduction

Background:

• The development of efficient photocatalysts for carbon dioxide (CO2) reduction is crucial for sustainable energy and environmental applications.
• Biscyclometalated Iridium(III) complexes are promising candidates for photocatalysis due to their unique photophysical properties.

Purpose of the Study:

• To synthesize and characterize a novel biscyclometalated Iridium(III) complex incorporating a triarylborane unit for CO2 reduction.
• To investigate the photocatalytic activity of the synthesized complex under visible light irradiation.

Main Methods:

• Synthesis of a biscyclometalated Iridium(III) complex featuring a covalently linked triarylborane moiety.
• Photocatalytic reduction of CO2 to CO and HCOOH using the Ir(III) complex and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (BIH) as a sacrificial reductant under visible light.

Main Results:

• The Ir(III) complex (IrDB) demonstrated efficient photocatalytic activity for the reduction of CO2 to CO and HCOOH.
• The presence of a direct covalent linkage between the Ir(III) metal center and the triarylborane unit was found to be essential for the observed photocatalytic performance.

Conclusions:

• A novel Ir(III) complex with an integrated triarylborane unit is an effective photocatalyst for CO2 reduction.
• The covalent linkage is a key design element for enhancing photocatalytic activity in CO2 reduction systems.