posted on 2021-02-03, 16:04authored byMingyang Hu, Ying Shu, Alexander Kirillov, Weisheng Liu, Lizi Yang, Wei Dou
The
integration of metal–organic frameworks (MOF) into organic
polymers represents a direct and effective strategy for developing
innovative composite materials that combine the exceptional properties
of MOFs with the robustness of organic polymers. However, the preparation
of MOF@polymer hybrid composites requires an efficient dispersion
and interaction of MOF particles with polymer matrices, which remains
a significant challenge. In this work, a new simple and direct approach
was applied for the development of Ln-MOF@polymer materials. A series
of Ln-MOF@TGIC composites {Ln-MOF = [Ln(μ3-BTC)(H2O)6]n (Ln-BTC), where
Ln = Eu, Tb, Eu0.05Tb0.95; H3BTC
= 1,3,5-benzenetricarboxylic acid; TGIC = triglycidyl isocyanurate}
were successfully obtained by applying a grinding method via the chemical
bonding between uncoordinated carboxylate groups in Ln-BTC and epoxy
groups in TGIC. The Ln-BTC@TGIC materials possess significant fluorescence
characteristics with superior emission lifetimes and quantum yields
if compared to parent Ln-MOFs. Interestingly, under the UV irradiation,
a considerable color change from yellow in Eu0.05Tb0.95-BTC to red in Eu0.05Tb0.95-BTC@TGIC
was observed. The energy-transfer mechanism was also rationalized
by the density functional theory (DFT) calculations. The developed
Ln-BTC@TGIC composites were further applied as functional fluorescent
coatings for the fabrication, via a simple spraying method, of the
flexible polyimide (PI) films, Ln-BTC@TGIC@PI. Thus, the present work
unveils a new methodology and expands its applicability for the design
and assembly of stable, multicomponent, and soft polymer materials
with remarkable fluorescence properties.