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The templated synthesis of porphyrin‐based oligomers and heterosystems is of considerable interest for materials with tunable electronic gaps, photovoltaics, or sensing device elements. In this work, temperature‐induced dehydrogenative coupling between unsubstituted free‐base porphine units and their attachment to graphene nanoribbons on a well‐defined Ag(111) support are scrutinized by bond‐resolved scanning probe microscopy techniques. The detailed inspection of covalently fused porphine dimers obtained by in vacuo on‐surface synthesis clearly reveals atomistic details of coupling motifs, whereby also putative reaction intermediates are identified. Moreover, the covalent attachment of porphines at preferred locations of atomically precise armchair‐type graphene nanoribbons is demonstrated. Interconnecting porphines and graphene nanoribbons: Porphine homocoupling and covalent attachment of porphines to graphene nanoribbons under atomically well‐defined on‐surface conditions was investigated by bond‐resolved scanning tunneling and atomic force microscopy. The thermally induced reactions on Ag(111) afford distinct coupling motifs, the relative abundance of which is associated with stepwise reaction mechanisms. [ABSTRACT FROM AUTHOR]

The orthogonal coordinative properties of tetrapyrrole macrocycles and nitrile ligands have been used in a multistep procedure towards interfacial d-f hetero-bimetallic nanoarchitectures based on a free-base porphyrin derivative functionalized with meso-cyanobiphenylene substituents. Molecular-level scanning tunneling microscopy studies reveal that the porphyrin module alone self-assembles on Ag(111) in a close-packed layer with a square unit cell. Upon co-deposition of Gd atoms, a square-planar motif is formed that reflects the fourfold coordination of CN ligands to the rare-earth centers. The resulting nanoporous network morphology is retained following exposure to a beam of Co atoms, which induces selective porphyrin metalation and ultimately yields a gridlike 2D metallosupramolecular architecture. [ABSTRACT FROM AUTHOR]