Charge Effects on the Structure and Composition of Porphyrin Binary Ionic Solids: ZnTPPS/SnTMePyP Nanomaterials

The pH of the solution from which a cooperative binary ionic material is formed can alter the charges of the organic anions and cations and thus the composition, crystal structure, and properties of the materials obtained by ionic self-assembly. In particular, this pH/charge effect provides a means of synthetic control over the properties and morphologies of ionic solids formed from cationic and anionic porphyrins. In the case of titration of an axial hydroxide ligand of the metal of the porphyrin to water, the charge increases by +1 with little perturbation of the molecular structure of the constituent porphyrin anion or cation. The structure of the material is thus altered without significantly altering the electronic structure of the porphyrin tecton. These novel porphyrin-based ionic materials have potential applications as catalysts, photocatalysts, and optoelectronic and sensing materials.