A visible-light harvesting system for CO2 reduction using a Ru(II) -Re(I) photocatalyst adsorbed in mesoporous organosilica.
Bottom Line: The embedded organic groups absorbed visible light, and the excitation energy was funneled to the Ru units.The energy accumulation was followed by electron transfer and catalytic reduction of CO2 to CO on the Re unit.The light harvesting of these hybrids enhanced the photocatalytic CO evolution rate by a factor of up to ten compared with that of RuRe adsorbed on mesoporous silica without a light harvester.
Affiliation: Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1-NE-1 O-okayama, Meguro-ku, Tokyo 152-8550 (Japan).Show MeSH
Mentions: Figure 1 A shows emission spectra of Acd–PMO and Ru−Re/Acd–PMO dispersions in MeCN for different amounts of adsorbed Ru−Re at an excitation wavelength of 405 nm. Approximately 88 % of these excitation photons were absorbed by Acd units, even for the highest amount of adsorbed Ru−Re (93 μmol g−1) (see the Supporting Information). In the absence of Ru−Re, Acd groups showed a maximum emission at 520 nm with a quantum yield (Φ) of 0.029. An increase in the adsorbed Ru−Re amount quenched the emission of the Acd units and enhanced a new emission band at around 640 nm, which resembled that of Ru−Re/MCM-41(I) upon excitation at 456 nm (Figure S9).
Affiliation: Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1-NE-1 O-okayama, Meguro-ku, Tokyo 152-8550 (Japan).