A photoinduced electron-transfer strategy for switchable fluorescence and phosphorescence in lanthanide-based...

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Luminescence

Background:

• Smart optical materials with tunable fluorescence and room temperature phosphorescence (RTP) are crucial for applications like intelligent switches and information security.
• Coordination polymers (CPs) offer versatile platforms for designing advanced functional materials.

Purpose of the Study:

• To synthesize a novel coordination polymer integrating dynamic fluorescence, switchable RTP, and photochromism.
• To investigate the manipulation of optical properties through photochromism for advanced applications.

Main Methods:

• Grafting a tetraimidazole derivative to lanthanum-diphosphonate via hydrogen bonds to form a 3D supramolecular CP.
• Characterizing the photophysical properties, including fluorescence and RTP, of the synthesized CP.
• Investigating the effect of photochromism on the material's luminescence.

Main Results:

• A novel CP, (H4-TIBP)·[La2Li(H2-HEDP)4(H-HEDP)]·3H2O, was synthesized with a 3D supramolecular structure.
• The CP exhibited dynamic fluorescence (blue to red) and switchable yellowish-green RTP, controllable by photochromism.
• Eu3+/Tb3+-doped CPs showed time-resolved red-to-yellow and green afterglow, respectively, due to multiple emission decay rates.

Conclusions:

• The synthesized CP successfully integrates color-adjustable fluorescence, switchable RTP, and photochromism in a single material.
• Photochromism enables effective manipulation of the material's optical performance.
• This work provides a pathway for designing smart optical materials for applications in optical communications, encryption, and anti-counterfeiting.