Multicolor Photoluminescence Including White-Light Emission by a Single Host-Guest Complex

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Photophysics

Background:

• Achieving multicolor and white-light photoluminescence from a single fluorescent compound under mild conditions is a significant challenge.
• Existing methods often require multiple components or complex setups.

Purpose of the Study:

• To develop a novel host-guest complex capable of stimuli-responsive multicolor photoluminescence.
• To achieve white-light emission using a single supramolecular platform.

Main Methods:

• Synthesis of a two-arm fluorescent guest molecule (BPC) with an asymmetrical donor-acceptor-donor structure.
• Complexation of BPC with gamma-cyclodextrin (γ-CD) to form the BPCY host-guest complex.
• Characterization using structural, spectroscopic, and computational simulation studies.

Main Results:

• The BPCY complex exhibits dual-sensitive luminescence, responding to excitation wavelength and the host molecule.
• Multicolor photoluminescence (red, green, blue) and tunable intermediate colors were achieved.
• Nearly pure white-light emission with CIE coordinates (0.33, 0.34) was generated.
• Mechanisms involve host-enhanced intramolecular charge-transfer (ICT) and host-induced restriction of intramolecular rotation (RIR).

Conclusions:

• The BPCY supramolecular complex demonstrates a novel strategy for achieving multicolor and white-light emission from a single platform.
• The host-guest interaction plays a crucial role in modulating the photoluminescence properties.
• This work provides a new molecular design rationale for high-performance optical materials with potential applications in information processing and display media.