Photoelectrochemical CO2 Reduction with Surface Immobilized Mn-NHC Complexes

The finite nature of fossil-fuel assets and the drive to dwindle the global carbon footprints are escalating research into alternative fuel and chemical production technologies.

One of the most studied approaches is transforming CO2 into a value-added product, which in turn lessens its abundance in the atmosphere.

Among all the existing CO2 reduction (CO2R) methods, the photoelectrochemical (PEC) is the most promising, as it uses abundant solar energy to convert CO2 into high-value chemicals, combining both the benefits of photocatalysis and electrocatalysis.

Nevertheless, there are only a few reports on the PEC-CO2R by molecular catalyst (majorly using noble metals Ru and Re) to produce CO, a crucial primary building block for chemicals with high technological and economic feasibility.

In this context, an electron-rich NHC-Mn(I)-carbonyl catalyst has been proposed for CO2R to produce CO with high selectivity at low overpotential and provide a potential platform to elucidate in-depth mechanistic studies, which are rare in this area. The sought mechanistic understanding can lead to the design of improved catalysts under optimal operating conditions.

The project will be implemented by a multifaceted approach involving synthesis, characterisation, catalysis, and computations and further enriched by the immobilisation of the catalyst on the semiconducting metal oxide surface to produce a suitable photocathode for PEC reduction of CO2.

We anticipate that this approach will deliver catalysts with a lower overpotential while maintaining the exceptional activity of the catalysts (TON, TOF, FE, QY).

The earth-abundant Mn-catalyst anchored on a heterogeneous surface can be integrated into devices for artificial photosynthesis by combining it with a suitable photoanode.

The project is also expected to lead to high-impact fundamental knowledge, and the results will be widely disseminated through publications in leading journals, symposia, conferences, and workshops.