In Situ Probing of CO2 Reduction on Cu-Phthalocyanine-Derived CuxO Complex

An in situ measurement of a CO2 reduction reaction (CO2RR) in Cu-phthalocyanine (CuPC) molecules adsorbed on an Au(111) surface is performed using electrochemical scanning tunneling microscopy. One intriguing phenomenon monitored in situ during CO2RR is that a well-ordered CuPC adlayer is formed into an unsuspected nanocluster via molecular restructuring. At an electrode potential of -0.7 V versus Ag/AgCl, the Au surface is covered mainly with the clusters, showing restructuring-induced CO2RR catalytic activity. Using a measurement of X-ray photoelectron spectroscopy, it is revealed that the nanocluster represents a Cu complex with its formation mechanism. This work provides an in situ observation of the restructuring of the electrocatalyst to understand the surface-reactive correlations and suggests the CO2RR catalyst works at a relatively low potential using the CuPC-derived Cu nanoclusters as active species.

Automated summary

This study performed in situ measurement of a CO2 reduction reaction in Cu-phthalocyanine molecules adsorbed on an Au surface using electrochemical scanning tunneling microscopy. The researchers observed the restructuring of the CuPC adlayer into unexpected nanoclusters during CO2RR, which showed catalytic activity. The nanoclusters were identified as Cu complexes based on X-ray photoelectron spectroscopy. The study provides insights into the surface-reactive correlations and suggests the use of CuPC-derived Cu nanoclusters as active species for CO2RR catalyst at a relatively low potential.