A Metal-Organic Framework derived CuxOyCz Catalyst for Electrochemical CO2 Reduction and Impact of Local pH Change

摘要

Developing highly efficient and selective electrocatalysts for the CO2 reduction reaction to produce value-added chemicals has been intensively pursued. We report a series of CuxOyCz nanostructured electrocatalysts derived from a Cu-based MOF as porous self-sacrificial template. Blending catalysts with polytetrafluoroethylene (PTFE) on gas diffusion electrodes (GDEs) suppressed the competitive hydrogen evolution reaction. 25 to 50 wt % teflonized GDEs exhibited a Faradaic efficiency of approximate to 54 % for C2+ products at -80 mA cm(-2). The local OH- ions activity of PTFE-modified GDEs was assessed by means of closely positioning a Pt-nanoelectrode. A substantial increase in the OH-/H2O activity ratio due to the locally generated OH- ions at increasing current densities was determined irrespective of the PTFE amount.