F. Guo et al.
Journal of Solid State Chemistry 277 (2019) 25–31
2. Experimental
which were further milled by the mortar. The dispersion of 1
(1 mg mLꢀ1) can be prepared by adding 3 mg of ground MOF 1 into
3 mL H2O and further stirred for 5 min. Luminescent intensity of ground
1 was collected in the absence or presence of various antibiotics in
aqueous solution (5.0 ꢂ 10ꢀ4 mol Lꢀ1, including sulfamethazine (SMZ),
chloramphenicol (CAP), thiamphenicol (THI), dimetridazole (DTZ),
penicillin (PCL), and nitrofurazone (NFZ). The emission spectra intensity
immediately detected after stirring about 2 min.
2.1. Materials and general methods
All chemical reagents and solvents herein were purchased from
commercial source, which all used without undergoing purification
process. Powder X-ray diffraction (PXRD) data were collected from
Rigaku D/Max-2500 diffractometer at 40 kV and 100 mA based on Cu-K
α
in the two theta range from 5ꢃ to 50ꢃ at room temperature. Thermog-
ravimetric analyses (TGA) result of fresh sample was acquired on
NETZSCH TG209 (Siemens) thermal analyzer from room temperature to
800 ꢃC and the heating rate is 10 ꢃC minꢀ1 under N2. Luminescent spectra
were measured on Cary Eclipse fluorescence spectrophotometer at out-
door temperature. UV–Vis absorption spectra can be achieved on Shi-
madzu UV-2700 spectrophotometer. Gas chromatograph data were
collected from Agilent 7890A gas chromatograph machine.
2.5. Typical procedure for luminescence titration
The ground samples (3 mg) were directly dispersed in 3 mL water to
obtain the dispersion of complex 1 (1 mg mLꢀ1), which was carefully
transferred to a quartz cell for the successional measurements. The
luminescent titration experiments were carried out by gradually adding
NFZ into the detectable system and repeated at least three cycles.
2.6. Recyclable luminescent experiment
2.2. Preparation of complex 1
The recyclability of MOF 1 after detecting NFZ was measured to
investigate its regeneration ability. After every sensing experiment,
reused MOF 1 was further recollected by easily centrifugation and
quickly washed with water for the successive quenching trial.
A mixture of L (23 mg, 0.05 mmol) and Zn(NO3)2ꢁ6H2O (20 mg,
0.067 mmol) was dissolved in N,N-Diethylformamide (DEF, 4 mL), which
was stirred about 30 min. The solution was sealed in a Teflon-lined
autoclave and heated at 100 ꢃC for three days. After cooling to outdoor
temperature, lots of block crystals were successfully generated. The as-
synthesized sample was washed with fresh DEF and further dried in air
for one day, which has high yield of 76% based on L linker.
2.7. Typical catalysis procedure
The dried complex 1 was immersed in toluene solvent for one day
before this catalytic reaction. In this catalysis procedure, substrate
(1 mmol) and malononitrile (1.1 mmol) were directly added into a 25 mL
round-bottom flask containing 6 mL toluene. The reaction temperature
arrived 85 ꢃC. Complex 1 (100 mg) was quickly putted into the reaction
flask and continually stirred during this whole reaction condition. The
catalytic yields were analysed by GC instrument.
2.3. X-ray data collection and structure refinement
Single crystal X-ray diffraction analysis of complex 1 were collected
on Bruker SMART CCD diffractometer equipped with Mo Kα
(λ ¼ 0.71073 Å). Crystal structure of 1 can be investigated and refined by
using a direct and full-matrix least squares method on F [2] with aniso-
tropic parameters for non-hydrogen atoms (SHELXL-2015) [43,44]
through OLEX2 program [45]. Further details for crystallographic data
and refinement information are all summarized in Table 1; meanwhile
CCDC 1910144 has the supplementary crystallographic data for complex
1, which can be achieved free of charge from The Cambridge Crystallo-
graphic Data Center.
2.8. Recyclable catalysis experiment
The reproducibility of catalytic 1 can be quickly recollected by
centrifugation, which was regenerated by simply washing with fresh
toluene. The recollected crystals were further reused as a base catalyst for
the next reaction.
2.4. Luminescent sensing experiment
3. Results and discussion
Before the luminescent sensing experiments, the as-synthesized
samples after washing with distilled water were directly dried in air,
3.1. Structural description for complex 1
Single X-ray crystallography illustrates that complex 1 based on L and
ZnII crystallizes in the orthorhombic system and Pnna space group. As
found in Fig. S1, the asymmetric unit contains one ZnII cation, one
crystallographically independent L linker, and one coordinated water
molecule. Notably, NOꢀ3 and DEF can't be directly located in the single X-
ray diffraction data, thus they don't discuss and display in the asymmetric
Table 1
Crystal data and structure refinement for 1.
Compound name
1
Sum formula
Mr
Crystal system
Space group
a (Å)
C24H18ON10Zn
527.85
orthorhombic
Pnna
28.580(6)
27.790(6)
9.6693(19)
90
90
90
7680(3)
8
0.913
unit. The bridging linker shows μ3- : :
η1 η1 η1 coordination mode (Fig. 1a).
As seen in Fig. 1b, each ZnII center is four-coordinated from three ni-
trogen atoms from three different bridging linkers, and one oxygen atom
from coordinated water, respectively. Three ZnII cations and three
bridging linkers can connect with each other to construct a hexagonal
channel along c axis (Fig. 1c). As illustrated in Fig. 1d and e, the 3D
network can be clearly found in complex 1.
b (Å)
c (Å)
α
(º)
β (º)
γ (º)
Volume (Å3)
Z
Dx (g cmꢀ3
)
)
3.2. PXRD and thermal analyses
Mμ
(mmꢀ1
0.664
Nref
9601
1.055
0.0593, 0.1897
0.0777, 0.2010
Powder X-ray diffraction (PXRD) results of complex 1 were measured
and collected at outdoor temperature. The data is clearly shown that the
diffraction peaks of as-synthesized 1 were significantly matched very
well with those of the simulated pattern from single crystal data, illus-
trating experimental samples are the phase purity and consist with the
S
R1a, wR2 [I > 2
σ
(I)]
b
R1a, wR2 (all data)
b
P
P
a
R1 ¼ jjFoj ꢀ jFcjj/ jFoj.
P
P
wR2 ¼ [ [w(F2o ꢀ Fc2)2]/ w(F2o)2]1/2
.
b
26