Sharing is Caring.... (^_^)

1. CONSTRUCTION OF LUMINESCENT TERBIUM
INORGANIC/ORGANIC MOLECULAR-BASED HYBRIDS
FROM MODIFIED FUNCTIONAL BRIDGE LIGAND
Bing Yan*, Li-Min Zhao.
Department of Chemistry, Tongji University, China (2004).
Source: Science Direct
NURUL ASHIKIN BT. ABD RAHMAN
D20091034935

2. 4-Tert-butylbenzoic acid (TBBA) was modified to achieve a functional
molecular bridge (TBBA-APMS) with double reactivity by the amidation
reaction by a cross-linking molecule (3-aminopropyl)trimethoxysilane
(abbreviated as APMS). The modified functional ligand further behaves
as a bridge which can both coordinate to terbium ion through amide’
oxygen atom and occur an in situ sol-gel process with matrix precursor
(tetraethoxysilane, TEOS), resulting a novel molecular hybrid material
(named as Tb-TBBA-APMS) with double chemical bond (Tb–O
coordination bond and Si–O covalent bond). Ultraviolet absorption,
phosphorescence, and fluorescence spectra were applied to
characterize the photophysical properties of the obtained hybrid
material. The strong luminescence of Tb3+ substantiates optimum
energy couple and effective intramolecular energy transfer between the
triplet state energy of modified ligand bridge and emissive energy level
of Tb3+ .

3. Inorganic-organic hybrid materials can devide into:
• Preparation & characterization of molecular hybrid material (Tb-TBBA-
APMS)
hydrolysis polycondensation So-gel technology
Chemical bonded with strong
covalent bond linking the
organic and inorganic.
Physically mixed with weak
interactions between the
organic and inorganic phases
So-gel technology: method for the preparation of inorganic-organic
hybrid materials

4. TBA-APMS
ethanol
+ TEOS
H2O
Tb(NO3)3.6H2O
diluted
hydrochloric
2 ml DMF +
hexamethylen
etetramine
60 C
Strir until
sample
solidified
Characterize the photophysical
properties of obtained hybrid material
Filter the product
formed

5. FTIR Spectrophotometer
• Measure Infrared
spectroscopy
Agilent Spectrophotometer
• Measure ultraviolet
absorption.
Perkin-Elmer
Spectrophotometer
• Measure fluorescence,
excitation and emission
spectra

6. AP
Ether,Pyridine, Ar
TBBA
TBBA-APMS
Preparation o f TBBA-APMS

7. Predicted Structure Of Hybrid Materials

8. Hydrolysis and polycondensation processes between TBBA-
APMS and TEOS

9. IR Spectra
Band located Characteristic
absorption
1688 cm-1 Acyl chloride
1640 cm-1 Amie group
(-CO-NH-)
Formation wavelength
Amide group stretching vibration
( vNH , 3376 cm-1) & bending
vibration (ᵹNH, 1554cm-1)
(Si-C) bond Stretching vibration : 1198
cm-1
Siloxane bonds absorption band at 1018 cm-1
(vSi–O–Si )

10. C
Ultraviolet absorption spectra
ii :258 nm
i: 248 nm
• Electron distribution of the
modified TBBA-APMS has hardly
changed compared to free TBBA
ligand for the introduction of
APMS group.
A: TBBA
B: TBBA-APMS
C: Tb-TBBA-APMS hybrids
• 10 nm (258-248 nm) is observed
on addition of Tb3+ to TBBA-A
PMS, proving the formation of a
complex between Tb3+ and TBBA -
APMS.

11. Phosphorescence spectra at 77K
TBBA
TBBA-APMS
• Different phosphorescence
bands correspond to different
ligand molecules
ii :424 nm
i :406 nm
• Modification of amino group
between A (406nm) and B
(424nm)

12. Excitation spectrum of Tb-TBBA-APMS hybrid material
A
B
C
D
A: 247.5 nm
B: 256.0 nm
C: 352.5 nm
D: 374.5 nm
Both these excitation
spectra bands are the
effective absorption for the
luminescence of Tb3+

13. Emission spectrum of Tb-TBBA-APMS hybrid materials
• Strong green luminescence
was observed .
• Effective energy transfer
between the aromatic ligand
TBBA-APMS and the chelated
Tb3+ ions.
488.5
543.5
583.0
621.5

14. • Hydrolysis and polycondensation reactions between
triethoxysilyl of TBBA-APMS and TEOS lead to the
formation of Si-O-Si network structures for the same
alkoxy groups.
• A novel luminescent molecular-based hybrid material with
double chemical bond was firstly constructed using TBBA-
APMS coordinated to Tb3+ .
• This technology can be expected to the assembly other
luminescent molecular-based hybrid material.

15. • T. Suratwala, Z. Gardlund, K. Davidson, D.R. Uhlmann,
Chem. Mater. 10 (1998) 190.
• C. Molina, K. Dahmouche, C.V. Santilli, Chem. Mater. 13
(2001) 2818.
• B. Yan, Q.Y. Xie, Inorg. Chem. Commun. 6 (2003) 1448.
• B. Yan, Q.Y. Xie, J. Mol. Struct. 688 (2004) 73.