Dual-color light emission and optical waveguide behavior in core-shell heterostructures based on surface doping of cocrystal with rare earth ions

Abstract

Organic core-shell structures/heterostructures are burgeoning as active photonic materials, i.e., optical waveguides, controllable multi-emissions, input-output optical logic gates. Here, a new conception that rare-earth (RE) ions as the surface dopants for the construction of organic cocrystal@RE complexes core-shell heterostructures was first proposed. Organic cocrystal Tpy-1,4-DITFB (Tpy = 2,2’:6′,2″-terpyridine; 1,4-DITFB = 1,4-diiodotetrafluorobenzenes) as inner-core has been designed. The RE ions of Eu(Ⅲ) and Tb(Ⅲ) are dopped on the surfaces of Tpy-1,4-DITFB cocrystal via epitaxial growth method. The effect of the compositions and morphologies of core-shell heterostructures on the optical behaviors were investagted via fluorescence spectroscopy. Spatially adjacent dual-color emission in the di-block core-shell heterostructures brings about tunable regulation of optical waveguide modes, offering potential applications for input/output optical logic gate and biomedical.