Lanthanide based white-light-emitting hydrogel mediated by fluorescein and carbon dots with high quantum yield and multi-stimuli responsiveness

Abstract

Stimuli-responsive materials, especially white-light emission (WLE) hydrogels, have aroused considerable attention in fabricating smart molecular machines, devices and materials. Herein, a lanthanide based WLE hydrogel with a high quantum yield and multi-stimuli responsiveness mediated by fluorescein and carbon dots is reported. Notably, a hydrogel with pure white emission is obtained by tailoring the stoichiometric ratio of lanthanide complex, fluorescein and carbon dots. The absolute quantum yield of our WLE hydrogel reaches as high as 18.00% through resonance energy transfer among the three primary colored emitters. The dynamic nature of coordination bonds of the lanthanide complex endows the hydrogel with multi-stimuli responsiveness to pH, Fe³⁺ and temperature. Our work provides a straightforward strategy to prepare smart white-light emission hydrogels.