Observation of divergent La{sup 3+} ion dilute effect in two series of 3-D fluorescent lanthanide-MOFs-based molecular alloys RE{sub x}La{sub 1−x}–EBTC (RE{sup 3+}=Eu{sup 3+} or Tb{sup 3+}; EBTC{sup 4−}=1,1′-ethynebenzene-3,3′,5,5′-etracarboxylate)

Journal Article · Thu Oct 15 00:00:00 EDT 2015 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2015.06.011· OSTI ID:22486785

Zhai, Lu ^[1]; Zhang, Wen-Wei ^[2]; Ren, Xiao-Ming ^[1]; Zuo, Jing-Lin ^[2]

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1. State Key Laboratory of Materials-Oriented Chemical Engineering and College of Science, Nanjing Tech University, Nanjing 210009 (China)
2. State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China)

The lanthanide metal-organic frameworks (MOFs) [Ln{sub 2}(EBTC){sub 1.5}(CH{sub 3}OH){sub 4}]·6H{sub 2}O are isostructural to each other, where EBTC{sup 4−}=1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylate; Ln{sup 3+}=La{sup 3+}, Eu{sup 3+} and Tb{sup 3+}; and the corresponding MOF is abbreviated as Ln–EBTC. MOFs Eu–EBTC and Tb–EBTC emit intense red and green luminescence (visible by bare eyes), respectively. The molecular alloys of Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC have been successfully prepared by mixing Eu{sup 3+}/Tb{sup 3+} and La{sup 3+} salts with the desired molar ratio in the starting material. Two series of Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC molecular alloys are isomorphic to the parent Ln–EBTC MOFs, while exhibit divergent La{sup 3+} ion diluting effect, namely, with increasing the relative amount of La{sup 3+}, the intensity of characteristic emission arising from Tb{sup 3+} ion monotonely increases in Tb{sub x}La{sub 1−x}–EBTC molecular alloys, whereas that of Eu{sup 3+} ion shows non-monotone decrease in Eu{sub x}La{sub 1−x}–EBTC molecular alloys. The possible origin is discussed for such a divergent behavior between Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC molecular alloys. - Graphical abstract: Two series of 3-D fluorescent lanthanide-MOFs-based molecular alloys RE{sub x}La{sub 1−x}–EBTC (RE{sup 3+}=Eu{sup 3+} or Tb{sup 3+}; EBTC{sup 4−}=1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylate) have been successfully prepared by mixing Eu{sup 3+}/Tb{sup 3+} and La{sup 3+} salts with the desired molar ratio in the starting material and showed photoluminescence property with divergent La{sup 3+} ion dilute effect. - Highlights: • 3-D molecular alloys of Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC were prepared. • They are isomorphic to the parent Ln–EBTC MOFs. • They show photoluminescence property with divergent La{sup 3+} ion diluting effect. • The possible origin is discussed for such a divergent behavior.

• OSTI ID: 22486785
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Vol. 230; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ACETYLENE
BENZENE
COORDINATION NUMBER
EUROPIUM COMPOUNDS
EUROPIUM IONS
FLUORESCENCE
HYDRATES
LANTHANUM COMPOUNDS
LANTHANUM IONS
METHANOL
ORGANOMETALLIC COMPOUNDS
PHOTOLUMINESCENCE
POLYMERS
RARE EARTH COMPLEXES
RHENIUM IONS
SALTS
TERBIUM COMPOUNDS
TERBIUM IONS