Molecular enhancement of heterogeneous CO2 reduction


The electrocatalytic carbon dioxide reduction reaction (CO2RR) addresses the need for storage of renewable energy in valuable carbon-based fuels and feedstocks, yet challenges remain in the improvement of electrosynthesis pathways for highly selective hydrocarbon production. To improve catalysis further, it is of increasing interest to lever synergies between heterogeneous and homogeneous approaches. Organic molecules or metal complexes adjacent to heterogeneous active sites provide additional binding interactions that may tune the stability of intermediates, improving catalytic performance by increasing Faradaic efficiency (product selectivity), as well as decreasing overpotential. We offer a forward-looking perspective on molecularly enhanced heterogeneous catalysis for CO2RR. We discuss four categories of molecularly enhanced strategies: molecular-additive-modified heterogeneous catalysts, immobilized organometallic complex catalysts, reticular catalysts and metal-free polymer catalysts. We introduce present-day challenges in molecular strategies and describe a vision for CO2RR electrocatalysis towards multi-carbon products. These strategies provide potential avenues to address the challenges of catalyst activity, selectivity and stability in the further development of CO2RR.

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Fig. 1: Molecularly enhanced heterogeneous CO2RR electrocatalysts.
Fig. 2: Classification of molecularly enhanced heterogeneous CO2RR electrocatalysts.
Fig. 3: Examples of action modes of molecular approaches on heterogeneous CO2RR catalysts.
Fig. 4: Future challenges for molecular strategies.


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This work was in part supported financially by the Natural Sciences and Engineering Research Council of Canada, the Ontario Research Fund: Research Excellence Program (ORF-RE-RE08-034), the Natural Resources Canada Clean Growth Program (CGP-17-0455) and CIFAR Bio-Inspired Solar Energy Program (FL-000719). This work was also supported by the Joint Center for Artificial Photosynthesis, a DOE Energy InnovationHub, supported through the Office of Science of the US Department of Energy under award no. DESC0004993, and was also based on work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under award no. OSR-2018-CPF-3665-03 and OSR-2019-CCF-1972.04. P.D.L. acknowledges the Natural Sciences and Engineering Research Council of Canada for support in the form of a Canada Graduate Scholarship and A.T. acknowledges the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Action H2020-MSCA-IF-2017 (793471).

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Nam, DH., De Luna, P., Rosas-Hernández, A. et al. Molecular enhancement of heterogeneous CO2 reduction. Nat. Mater. 19, 266–276 (2020).

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