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Iron Porphyrin Allows Fast and Selective Electrocatalytic Conversion of CO 2 to CO in a Flow Cell
Author(s) -
Torbensen Kristian,
Han Cheng,
Boudy Benjamin,
Wolff Niklas,
Bertail Caroline,
Braun Waldemar,
Robert Marc
Publication year - 2020
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.202000160
Subject(s) - overpotential , selectivity , catalysis , current density , porphyrin , electrochemistry , electrocatalyst , inorganic chemistry , materials science , carbon black , chemistry , carbon fibers , analytical chemistry (journal) , chemical engineering , electrode , photochemistry , organic chemistry , composite material , physics , natural rubber , quantum mechanics , composite number , engineering
Molecular catalysts have been shown to have high selectivity for CO 2 electrochemical reduction to CO, but with current densities significantly below those obtained with solid‐state materials. By depositing a simple Fe porphyrin mixed with carbon black onto a carbon paper support, it was possible to obtain a catalytic material that could be used in a flow cell for fast and selective conversion of CO 2 to CO. At neutral pH (7.3) a current density as high as 83.7 mA cm −2 was obtained with a CO selectivity close to 98 %. In basic solution (pH 14), a current density of 27 mA cm −2 was maintained for 24 h with 99.7 % selectivity for CO at only 50 mV overpotential, leading to a record energy efficiency of 71 %. In addition, a current density for CO production as high as 152 mA cm −2 (>98 % selectivity) was obtained at a low overpotential of 470 mV, outperforming state‐of‐the‐art noble metal based catalysts.