Excimer formation in a 2D confined space

Abstract

Combination of organic dyes with 2D materials can lead to integrations forming heterostructures with tunable properties, where organic dyes, with their distinct energy levels and high absorption, can enhance the performance of 2D material-based optoelectronic devices. This manuscript focuses on the confinement-induced changes of such structures containing 4,4’-(2,6-naphthalenediyl)dipyridine dications capable to form excimer species within the 2D interlayer space of synthetic saponite. The interlayer space provides an interesting microenvironment enabling to control optical properties of the intercalated organic molecules by either varying their amount or expanding the interlayer space via swelling with aprotic solvents, resulting in stimuli-responsive materials. Utilization of spectroscopic techniques, statistical analysis, and theoretical methods revealed distinct features corresponding to the relative presence of different species with unique spatial arrangements. Depending on the occupancy of the interlayer space, the subsequent application of dimethyl sulfoxide leads to a swelling of the interlayer space, affecting the orientation and relative distribution of species. Presented study also highlights the importance of in-depth analysis of organic species in confined environments of 2D materials, contributing to the optimization and development of novel applied materials.