Photodriven Electron Transport within the Columnar Perylenediimide Nanostructures Self-Assembled with Sulfonated Porphyrins in Water

Abstract

Columnar stacks of <i>N</i>,<i>N</i>′-di­(2-(trimethylammoniumiodide)­ethylene) perylenediimide (TAIPDI)_<i>n</i> can host <i>meso</i>-tetrakis­(4-sulfonatophenyl)­porphyrin zinc tetrapotassium salt (ZnTPPSK₄) molecules at different ratios through the ionic and π–π interactions prompted by an aqueous environment. Photoexcitation of this host–guest complex generates very fast charge separation (1.4 × 10¹² s^–1). Charge recombination is markedly decelerated by a probable electron delocalization mechanism along the long-range of tightly stacked TAIPDIs (4.6 × 10⁸ s^–1), giving an exceptional <i>k</i>_CS/<i>k</i>_CR ratio of 3000 as determined by using time-resolved transient absorption techniques