The manufacture of high-performance photocatalytic systems based on earth-abundant elements remains a key challenge, urging operative strategies for catalyst design. Herein, we present the construction of an efficient and noble-metal-free molecular system for the photoreduction of CO2 to CO using a Cu(I) photosensitizer and Co(II) phthalocyanine catalysts. It was found that the perfluorination of Co(II) phthalocyanine shows enhanced catalytic performance for CO2-to-CO conversion compared with pristine Co(II) phthalocyanines, achieving a remarkable apparent quantum yield of 58.2% at 425 nm, which is three times that of the pristine one (19.0%). The Cu(I)/Co(II) system also achieved a maximum turnover number of 9185 and near-unity selectivity. These improvements can be attributed to the electron-withdrawing effect of the fluorine substituents, which lowers the catalytic overpotential for catalysis and decreases the Gibbs free energy of the rate-determining Co-carboxylate-forming step. This work indicates that perfluorination is an effective approach to optimize the catalytic performance of molecular catalysts. Published by Elsevier B.V. All rights reserved.
Enhancing CO2 photoreduction via the perfluorination of Co(II) phthalocyanine catalysts in a noble-metal-free system
Chin. J. Catal. 2023, 49, 160-167, DOI: 10.1016/S1872-2067(23)64433-X.