Construction and modulation of dual responsive fluorescent aggregates combined with molecular dynamics simulation

Abstract

Abstract The fluorescent functional material prepared by combining 16‐alkyl (ferrocenyl‐methyl) ammonium bromide (Fc16AB) and dye molecule Congo red (CR) via ionic self‐assembly strategy exhibits double stimuli‐responsive behavior triggered by redox and pH value. Both the fabrication and switching mechanism of aggregates are proposed according to the cooperative binding of noncovalent interactions, including π‐π stacking, electrostatic interactions, charge transfer interaction, and amphiphilic hydrophobic association. The optimal geometry and energy transfer between monomers and aggregate are studied by means of quantum chemistry calculation and wavefunction analysis, which provides a deep and theoretical understanding for formation mechanism of ionic self‐assemblies. Moreover, the fluorescent switching behavior of assemblies upon pH was studied in detail, which opens the new way for the construction of organic light‐emitting diode (OLED).

Keywords

• ionic self‐assembly
• pH
• quantum chemistry calculation
• redox species
• stimuli‐responsive