Conductive Two-Dimensional Phthalocyanine-based Metal-Organic Framework Nanosheets for Efficient Electroreduction of CO2

Abstract

The electrocatalytic conversion of CO₂ into value-added chemicals is a promising approach to realize a carbon-energy balance. However, low current density still limits the application of the CO₂ electroreduction reaction (CO₂ RR). Metal-organic frameworks (MOFs) are one class of promising alternatives for the CO₂ RR due to their periodically arranged isolated metal active sites. However, the poor conductivity of traditional MOFs usually results in a low current density in CO₂ RR. We have prepared conductive two-dimensional (2D) phthalocyanine-based MOF (NiPc-NiO₄ ) nanosheets linked by nickel-catecholate, which can be employed as highly efficient electrocatalysts for the CO₂ RR to CO. The obtained NiPc-NiO₄ has a good conductivity and exhibited a very high selectivity of 98.4 % toward CO production and a large CO partial current density of 34.5 mA cm^-2 , outperforming the reported MOF catalysts. This work highlights the potential of conductive crystalline frameworks in electrocatalysis.

Keywords: CO; conductive metal-organic frameworks; electroreduction; phthalocyanine.