1 research outputs found
Selective Photocatalytic CO<sub>2</sub> Reduction in Water through Anchoring of a Molecular Ni Catalyst on CdS Nanocrystals
Photocatalytic conversion of CO<sub>2</sub> into carbonaceous feedstock
chemicals is a promising strategy to mitigate greenhouse gas emissions
and simultaneously store solar energy in chemical form. Photocatalysts
for this transformation are typically based on precious metals and
operate in nonaqueous solvents to suppress competing H<sub>2</sub> generation. In this work, we demonstrate selective visible-light-driven
CO<sub>2</sub> reduction in water using a synthetic photocatalyst
system that is entirely free of precious metals. We present a series
of self-assembled nickel terpyridine complexes as electrocatalysts
for the reduction of CO<sub>2</sub> to CO in organic media. Immobilization
on CdS quantum dots allows these catalysts to be active in purely
aqueous solution and photocatalytically reduce CO<sub>2</sub> with
>90% selectivity under UV-filtered simulated solar light irradiation
(AM 1.5G, 100 mW cm<sup>–2</sup>, λ > 400 nm, pH 6.7,
25 °C). Correlation between catalyst immobilization efficiency
and product selectivity shows that anchoring the molecular catalyst
on the semiconductor surface is key in controlling the selectivity
for CO<sub>2</sub> reduction over H<sub>2</sub> evolution in aqueous
solution