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Abstract The reduction of dioxygen to produce selectively H2O2or H2O is crucial in various fields. While platinum‐based materials excel in 4H+/4e−oxygen reduction reaction (ORR) catalysis, cost and resource limitations drive the search for cost‐effective and abundant transition metal catalysts. It is thus of great importance to understand how the selectivity and efficiency of 3d‐metal ORR catalysts can be tuned. In this context, we report on a Co complex supported by a bisthiolate N2S2‐donor ligand acting as a homogeneous ORR catalyst in acetonitrile solutions both in the presence of a one‐electron reducing agent (selectivity for H2O of 93 % and TOFi=3 000 h−1) and under electrochemically‐assisted conditions (0.81 V <η<1.10 V, selectivity for H2O between 85 % and 95 %). Interestingly, such a predominant 4H+/4e−pathway for Co‐based ORR catalysts is rare, highlighting the key role of the thiolate donor ligand. Besides, the selectivity of this Co catalyst under chemical ORR conditions is inverse with respect to the Mn and Fe catalysts supported by the same ligand, which evidences the impact of the nature of the metal ion on the ORR selectivity.
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Simultaneous CO 2 capture and functionalization: solvated electron precursors as novel catalysts
Metal complexes with diffuse solvated electrons (solvated electron precursors) are proposed as alternative catalysts for the simultaneous CO 2 capture and utilization. Quantum chemical calculations were used to study the reaction of CO 2 with H 2 and C 2 H 4 to produce formic acid, methyldiol and δ-lactone. Mechanisms of a complete reaction pathway are found and activation barriers are reasonably low. The metal ligand complex readily reduces CO 2 and significantly stabilizes CO 2 ˙ − . Ligand identity minimally influences the reaction. Additional reactions and future strategies are proposed with the goal of inducing experimental interest.
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- Award ID(s):
- 1940456
- PAR ID:
- 10329650
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 58
- Issue:
- 9
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 1310 to 1313
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1CC04748E
