Interfacial structure of Co porphyrins on Au(111) electrode: Interaction of porphyrin molecules with substrate

► Detailed structures of CoOEP and CoP were determined using X-ray diffraction. ► The adsorption of porphyrin prefers interaction through the π electrons‐substrate. ► The adsorption energy of CoOEP is comparable to that of CoP. ► The porphyrin with high density causes a lifting to a complete 1 × 1 structure.