Stereoselective Photopolymerization of Tetraphenylporphyrin Derivatives on Ag(110) at the Sub‐Monolayer Level |
| |
Authors: | Andrea Basagni Luciano Colazzo Francesco Sedona Marco DiMarino Prof Tommaso Carofiglio Elisa Lubian Daniel Forrer Andrea Vittadini Prof Maurizio Casarin Alberto Verdini Albano Cossaro Luca Floreano Prof Mauro Sambi |
| |
Institution: | 1. Dipartimento di Scienze Chimiche, Università di Padova, Via Marzolo 1, 35131, Padova (Italy);2. Consorzio INSTM, Via Marzolo 1, 35131 Padova (Italy);3. CNR‐IENI, Via Marzolo 1, 35131 Padova (Italy);4. Laboratorio Nazionale TASC, Area Science Park, S. S. 14, km 163.5, 34149 Trieste (Italy) |
| |
Abstract: | We explore a photochemical approach to achieve an ordered polymeric structure at the sub‐monolayer level on a metal substrate. In particular, a tetraphenylporphyrin derivative carrying para‐amino‐phenyl functional groups is used to obtain extended and highly ordered molecular wires on Ag(110). Scanning tunneling microscopy and density functional theory calculations reveal that porphyrin building blocks are joined through azo bridges, mainly as cis isomers. The observed highly stereoselective growth is the result of adsorbate/surface interactions, as indicated by X‐ray photoelectron spectroscopy. At variance with previous studies, we tailor the formation of long‐range ordered structures by the separate control of the surface molecular diffusion through sample heating, and of the reaction initiation through light absorption. This previously unreported approach shows that the photo‐induced covalent stabilization of self‐assembled molecular monolayers to obtain highly ordered surface covalent organic frameworks is viable by a careful choice of the precursors and reaction conditions. |
| |
Keywords: | covalent organic frameworks on‐surface synthesis porphyrins scanning tunneling microscopy (STM) surface photochemistry surface polymerization |
|
|