(602b) Bottom-up Vapor-Phase Synthesis of Porphyrin-Based Covalent Organic Frameworks

Porphyrins and their derivatives have attracted many researchers’ attention as they are precursors for the preparation of covalent organic frameworks (COFs). It has been demonstrated that porphyrin and its metal complexes can be employed as electrocatalysts, especially for oxygen reduction and carbon dioxide reduction reactions. In addition, these materials have also been explored in photocatalysis, separation, optical switches and so on. Polymerization of porphyrins to create frameworks and networks increases the stability of these materials, thus preparing porphyrins-based COFs is important to their widespread applications. COFs are commonly synthesized via the solvothermal method, which involves very long reaction time and the usage of toxic organic solvents. Herein, we report the one-step, solvent-free synthesis of crystalline and porous porphyrin-based COFs. Both 5,10,15,20-tetra(4-aminophenyl)porphyrin (TAPP) and its transition metal complex (MPOR-COF, M = Cu, Co) in the presence of a Lewis acid were polymerized to form polymer networks. The electron microscopy of the deposited films showed that the film contains both amorphous and crystalline domains. The crystalline domain was characterized and proved to be a COFs, composed of 2D films of the phenazine-linked TAPPs that are stacked with the π-π interactions at a distance of 0.3 nm. The processing parameters of our vapor phase reaction were searched, and we note control over the nucleation site on the substrate such as sapphire and silicon. The materials were further coated on glassy carbon and tested for its photoelectrocatalytic properties. Here we report on the synthetic parameters and the correlation between precursor design and electroactivities.