High-selectivity turn-on fluorescence-based fluoride ion detection using histidine-functionalized UiO-66-NH.

Hisditine-functionalized UiO-66-NH (UiO-66-NH@Hst) as a novel "turn-on" fluorescent probe to detect fluoride ions has been successfully synthesized using the solvothermal method. The results showed that fluoride ion detection gave the best fluorescence response in water media and no response was observed in non-polar solvents. Detection at pH 3-10 produces a relatively similar fluorescence response and decreases quite significantly at pH 11-13.

Crystal growth of the core and rotated epitaxial shell of a heterometallic metal-organic framework revealed with atomic force microscopy.

Atomic force microscopy has been used to determine the surface crystal growth of two isostructural metal-organic frameworks, [Zn(ndc)(dabco)] (ndc = 1,4-naphthalenedicarboxylate, dabco = 4-diazabicyclo[2.2.2]octane) (1) and [Cu(ndc)(dabco)] (2), from a core crystal of 1 for the former and a core-shell 1@2 crystal for the latter.

Unveiling the mechanism of lattice-mismatched crystal growth of a core-shell metal-organic framework.

Determining the effect of severe lattice mismatch on the crystal growth mechanism and form of epitaxially grown materials is vital to understand and direct the form and function of such materials. Herein, we report the use of atomic force microscopy to reveal the growth of a shell metal-organic framework (MOF) on all faces of a core MOF that has similar , -lattice parameters but a ∼32% mismatch in the -lattice parameter. The work shows the mechanism through which the shell MOF overcomes the core terrace height mismatch depends on that mismatch being reduced before overgrowth of continuous shell layers can occur.