Spatial Confinement in Copper-Porphyrin Frameworks Enhances Carbon Dioxide Reduction to Hydrocarbons

Abstract

Summary: Porphyrin-based catalysts are promising for electrochemical carbon dioxide (CO2) conversion. We report here molecular Cu-porphyrin-constructed porous frameworks for efficient CO2 reduction. This framework catalyst has a high Faradaic efficiency of 73.6% and a partial current density of 7.5 mA cm−2 at −1.4 V versus RHE for the selective production of hydrocarbons, while only carbon monoxide is generated on the Cu-porphyrin building blocks. Experimental results demonstrate that this porous framework has a high CO2 absorption capability, and abundant copper-active sites account for the efficient CO2 conversion. Moreover, finite-element simulations reveal that the spatial confinement of CO intermediates in the porous framework are critical for the efficient generation of hydrocarbons. This work may offer insights into designing efficient catalysts for CO2 reduction to valuable products.

Keywords

• CO2 electroreduction
• electrocatalysis
• Cu-porphyrin frameworks
• spatial confinement
• hydrocarbon
• metal centers