A Stable Extra-Large-Pore Zeolite with Intersecting 14- and 10-Membered-Ring Channels

Article abstract of DOI:10.1002/chem.201602419

The development of inorganic frameworks with extra-large pores (larger than 12-membered rings) has attracted considerable attention because of their potential applications in catalysis, the separation of large molecules, and so forth. We herein report the synthesis of the new extra-large-pore zeolite NUD-2 by using the supramolecular self-assembly of simple aromatic organic cations as structure-directing agents (SDAs). NUD-2 is a high-silicon-content germanosilicate with interconnecting 14×10-membered-ring channels. The SDAs in NUD-2 can be removed by calcination in air at 550 °C to yield permanent pores with a BET surface area of 500 m²g^?1. Both germanium and organic cations in NUD-2 can also be removed by treatment with acid at lower temperature, thus not only affording recycling of germanium and SDAs, but also providing a highly stable siliceous zeolite. In addition, aluminum ions can be incorporated into the framework of NUD-2. The NUD-2 structure is yet another extra-large-pore zeolite synthesized by using the supramolecular self-assembling templating approach, thus demonstrating that this approach is a general and applicable strategy for synthesis of new large- and extra-large-pore zeolites.

Full text of DOI:10.1002/chem.201602419

DOI: 10.1002/chem.201602419
Full Paper
&
Microporous Materials
A Stable Extra-Large-Pore Zeolite with Intersecting 14- and 10-
Membered-Ring Channels
Zi-Hao Gao+,[a] Fei-Jian Chen+,[a, c] Lei Xu,[a] Lin Sun,[a] Yan Xu,*[b] and Hong-Bin Du*[a]
Abstract: The development of inorganic frameworks with
extra-large pores (larger than 12-membered rings) has at-
tracted considerable attention because of their potential ap-
plications in catalysis, the separation of large molecules, and
so forth. We herein report the synthesis of the new extra-
large-pore zeolite NUD-2 by using the supramolecular self-
assembly of simple aromatic organic cations as structure-di-
recting agents (SDAs). NUD-2 is a high-silicon-content ger-
manosilicate with interconnecting 14ꢀ10-membered-ring
channels. The SDAs in NUD-2 can be removed by calcination
in air at 5508C to yield permanent pores with a BET surface
area of 500 m2gÀ1. Both germanium and organic cations in
NUD-2 can also be removed by treatment with acid at lower
temperature, thus not only affording recycling of germanium
and SDAs, but also providing a highly stable siliceous zeolite.
In addition, aluminum ions can be incorporated into the
framework of NUD-2. The NUD-2 structure is yet another
extra-large-pore zeolite synthesized by using the supra-
molecular self-assembling templating approach, thus dem-
onstrating that this approach is a general and applicable
strategy for synthesis of new large- and extra-large-pore zeo-
lites.
Introduction
Rigid bulky OSDAs with the appropriate polarity/hydrophilicity
have been shown to be effective in the synthesis of extra-
large-pore zeolites, such as the high-silica-content zeolites with
14-membered-ring (14R) pores UTD-1[8] and CIT-5[9] and SSZ-61
with 18-membered-ring (18R) pores,[10] among others. Howev-
er, bulky OSDAs are usually expensive and not readily available
and the preparations of these OSDAs often involve tedious
multistep reactions, thus producing low total yields. Moreover,
as the size of an OSDA increases, its hydrophobicity often in-
creases, which limits its solubility and diminishes its ability as
an OSDA for the formation of zeolites. The presence of heter-
oatoms such as beryllium, boron, gallium, and germanium
during the zeolite synthesis, on the other hand, aids the forma-
tion of 3-membered rings (3R) or double-4-membered rings
(D4R) and has been deemed to be the key to the synthesis of
some of these extra-large-pore zeolites.[4–7] A number of extra-
large-pore zeolites have been prepared by using this strategy,
for example, OSB-1 (Be; 14R),[11] SSZ-53 and SSZ-59 (B; 14R),[12]
ECR-34 (Ga; 18R),[13] IM-12 (Ge; 14R),[14] GeZA (Ge; 15R),[15] NUD-
1 (Ge; 18R),[16] PKU-12 (Ge; 20R),[17] and the ITQ series (Ge; 16R,
18R, 20R, 28R, and 30R).[18] However, the presence of these het-
eroatoms in the zeolite frameworks often limited their chemi-
cal properties and thermal stabilities that hinder their use as
potential catalysts. To address this issue, postsynthetic modifi-
cation by means of the isomorphous substitution of aluminum
or silicon for germanium has been applied to some germanosi-
licates to yield highly stable aluminosilicate or siliceous zeo-
lites.[19] Nonetheless, only a few stable extra-large-pore zeolites
have been produced so far.
Extra-large-pore (consisting of more than 12 tetrahedra) zeo-
lites have long attracted the attention of both chemists and in-
dustrial entrepreneurs because of their potential applications
in the hydrocracking of heavy-oil fractions, the production of
fine chemicals, biomass processes, shape-selective catalysis,
the separation of large molecules, and so forth.[1,2] The past de-
cades have witnessed the miraculous development of the syn-
thesis of extra-large-pore zeolites, with more than 16 extra-
large-pore silicate-based zeolites reported to date.[3] However,
the synthesis of stable extra-large-pore zeolites remains a chal-
lenge.[4–7]
The recent successful synthesis of extra-large-pore zeolites is
mainly due to the use of exotic organic structure-directing
agents (OSDAs) and heteroatoms during their synthesis.[4–7]
[a] Z.-H. Gao,+ Dr. F.-J. Chen,+ L. Xu, L. Sun, Prof. H.-B. Du
State Key Laboratory of Coordination Chemistry
Collaborative Innovation Center of Chemistry for Life Sciences
School of Chemistry and Chemical Engineering
Nanjing University, Nanjing, 210093 (P.R. China)
E-mail: hbdu@nju.edu.cn
[b] Prof. Y. Xu
College of Chemistry and Chemical Engineering
State Key Laboratory of Materials-Oriented Engineering
Nanjing Tech University, Nanjing, 210009 (P.R. China)
E-mail: yanxu@njtech.edu.cn
[c] Dr. F.-J. Chen+
Department of Chemistry, Bengbu Medical College
Bengbu, 233030 (P.R. China)
[+] These authors contributed equally to this work.
Recently, we prepared an extra-large-pore germanosilicate
zeolite NUD-1 with intersecting 18-, 12-, and 10-R channels by
using an approach based on the supramolecular self-assembly
Supporting information for this article can be found under
http://dx.doi.org/10.1002/chem.201602419.
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of small aromatic organic cations as SDAs.[16] The supramolec-
ular-assembly templating (SAT) approach has been noted by
others during the synthesis of the high-silica-content zeolite
ITQ-29,[20] the AlPO4-LTA molecular sieve, and the large-pore
AlPO4-5,[21] in which supramolecular assemblies of aromatic
cations occurred and acted as SDAs. This approach can also be
applied to the synthesis of the extra-large-pored zeolite ITQ-
37.[22] By using the supramolecular self-assembly of the small
aromatic organic cation 1-methyl-3-(2’-methylbenzyl)imidazoli-
um as an OSDA, we recently prepared a new stable extra-
Single-crystal X-ray diffraction analyses show that NUD-2
crystallizes in the orthorhombic space group C222 with a=
13.762(2), b=27.452(4), and c=5.1170(5) ꢂ. The structure of
NUD-2 is constructed of two-dimensional sheets and D4R units
(Figure 2). The two-dimensional sheets are made of two types
of interconnecting parallel one-dimensional zigzag SiO4 chain
along the crystallographical c axis. The sheets are perpendicu-
lar to the b axis and consist of composite building units (CBU)
cas or ton (i.e., 5462 or 546281 cages, respectively). The sheets
are stacked in an ABAB manner along the b axis and intercon-
nected by D4R units to form a two-dimensional pore system,
with intersecting 14R and 10R channels along the c and a axes
(Figure 2b), respectively.
large-pore
germanosilicate
zeolite
[Ge4Si28O64F]·(C12H15N2)(C12H15N2F)1.20, named NUD-2, with inter-
secting 14- and 10-R channels. The NUD-2 zeolite is a germano-
silicate with a molar ratio of Ge/Si as low as 0.1:1, from which
the highly stable aluminosilicate and siliceous zeolite NUD-2
can be obtained by postsynthetic modification. It is noted that
Boal et al. reported the synthesis of CIT-13 by using a similar
synthetic system during the preparation of this report.[23] The
preliminary report by Boal et al. showed that CIT-13 is isostruc-
tural to NUD-2. Herein, we report our detailed studies on the
single-crystal structure and properties of NUD-2.
The NUD-2 zeolite is closely related to the 14R-pore zeolites
IM-12[14] or ITQ-15[24] (zeolite framework code=UTL) and CIT-
5[9] (CFI), all of which are built on the similar two-dimensional
sheets of interconnecting parallel one-dimensional zigzag SiO4
chains (Figure 2). The two-dimensional sheets are stacked par-
allel in an ABAB manner and linked to form 14R channels. The
sheets in NUD-2 and CIT-5 are basically the same, that is, com-
posed of cas or ton CBUs. In NUD-2, the two-dimensional
sheets are linked by D4R units through every other silicon-
center vertex along the c axis to form one-dimensional 14R
channels with intersecting 10R channels along the a axis. In
CIT-5 (CFI), the two-dimensional sheets are linked by the so-
called double zigzag chains (DZCs; parallel to the b axis), thus
forming one-dimensional 14R channels along the c axis, with
no open channels in other directions. In IM-12 or ITQ-15 (UTL),
on the other hand, the two-dimensional sheets are made of
two CBUs ton and fer (i.e., a 5661 cage), which are linked by
D4R units through every three silicon vertexes in two-dimen-
sional sheets to form one-dimensional 14R channels with inter-
secting 12R channels along the b axis. The pore size of the 14R
channel in NUD-2 is 8.3ꢀ6.8 ꢂ, which is close to the pore sizes
of UTL and CFI (i.e., 9.5ꢀ7.1 and 7.5ꢀ7.2 ꢂ, respectively). The
10R channel in NUD-2 is elliptical, with a pore size of 3.6ꢀ
6.7 ꢂ. The framework density (FD) of NUD-2 is 16.5 T atoms per
1000 ꢂ3, which is larger than those of UTL (15.2 T), but less
than the other 14R zeolites UTD-1, CFI, SZZ-53, and SSZ-59
(17.1, 16.8, 17.9, and 17.8 T, respectively).
Results and Discussion
The NUD-2 zeolite can be synthesized by using either 1-
methyl-3-(2’-methylbenzyl)imidazolium (SDA1) or 1-methyl-3-
(3’-methylbenzyl)imidazolium (SDA2) as OSDAs in the presence
of germanium and fluoride ions (see the Experimental Section).
The best-crystallized pure phase of NUD-2 was obtained with
a gel composition of 1:0.2:(0.75–1):(0.75–1):10 of SiO2/GeO2/
SDA(OH)/HF/H2O at 1508C for 15 days. Large platelet crystals
of NUD-2 suitable for single-crystal X-ray diffraction analysis
were obtained for SDA2 (see Figure S1 in the Supporting Infor-
mation). Figure 1shows the X-ray powder diffraction (XRPD)
pattern of the as-synthesized NUD-2, which is in good agree-
ment with the calculated patterns from the single-crystal struc-
tural data.
The structural refinements of the single-crystal diffraction
data showed that the germanium ions in NUD-2 preferentially
occupy positions in the D4R units, similar to other gemanosili-
cate zeolites.[16] Of the six crystallographically independent
Tsites in NUD-2, each T atom (T3 and T4) in D4Rs are 50% ger-
manium and 50% silicon, whereas the other T atoms (T1, T2,
T5, and T6) in the layer are basically pure silicon. At the center
of each D4R unit, a fluoride ion was located during the struc-
tural refinement. Consistently, the solid-state 19F NMR spectra
of the as-synthesized NUD-2 (Figure 3) showed a strong reso-
nance band at d=À7.2 ppm owing to the fluoride ion present
in the D4R. An additional peak at d=À124.0 ppm in the
19F NMR spectra is attributed to mobile fluoride ions in the
channels, which act as charge-balancing counterparts for the
OSDA cations. Solid-state 13C NMR spectra of the as-synthe-
sized NUD-2 (see Figure S2 in the Supporting Information)
showed that intact OSDA cations were present in the product.
Figure 1. XRPD patterns of a) calcined, b) as-synthesized, and c) calculated
NUD-2 based on single-crystal diffraction data. The sample was synthesized
from SiO2/GeO2/SDA2(OH)/HF/H2O (1:0.2:1:1:10) at 1508C for 15 days.
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Figure 2. Structure presentations of NUD-2. a) Two-dimensional sheets made of interconnecting parallel one-dimensional zigzag SiO4 chains. b) Zeolite NUD-2
is shown to be built upon connections between the layers and D4Rs, thus forming intersecting 14R and 10R channels. c) Zeolite CFI is shown to be built
upon connections between the layers and the DZCs, thus forming the 14R channels. d) Zeolite UTL is shown to be built upon connections between the
layers and D4Rs, thus forming intersecting 14R and 12R channels. O=red, Si (Ge)=gray or cynan, F=green. The disordered ions in NUD-2 are drawn in one
of the two only possible locations.
structure refinement and analysis by TGA, NMR spectroscopy,
and energy-dispersive spectrometry (EDS), the formula of the
as-synthesized NUD-2 used for the single-crystal diffraction
analyses can be deduced as [Ge4Si28O64F]·(C12H15N2)
(C12H15N2F)1.20
.
Because of relatively high Si/Ge ratio, NUD-2 is stable in
a dry atmosphere after calcination at high temperature to
remove the organic templates (see the XPRD images in
Figure 1). The nitrogen (argon) adsorption of the calcined
NUD-2 (see Figure 4 and Figure S4 in the Supporting Informa-
tion) gave the BET surface area of 357 (500) m2 gÀ1 and a total
pore volume of 0.162 (0.228) cm3 gÀ1. The mean pore size of
NUD-2 is about 7.8 ꢂ, obtained by applying the density-func-
tional theory (DFT)[25] to the argon adsorption isotherm.
It is interesting to note that both the germanium and organ-
ic cations in NUD-2 can be removed by treatment with acid,
that is, by using procedures that have been applied to some
germanosilicates to yield highly stable aluminosilicate or sili-
ceous zeolites.[19] After the as-synthesized NUD-2 was treated
in concentrated hydrochloric acid in the presence of a small
amount of tetraethylorthosilicate at 443 K for 24 hours, approx-
imately 76.2% of the organic templates were removed (see
Figure S3 in the Supporting Information). Interestingly, the re-
moved organic templates remained intact (see Figure S5 in the
Supporting Information), thus suggesting recyclability of these
Figure 3. Solid-state 19F NMR spectrum of the as-synthesized SDA2-NUD-2.
Peaks marked with an asterisk are spin bands.
Thermogravimetric analysis (TGA) showed a weight loss of
17.7% owing to the removal of organic templates (see Fig-
ure S3 in the Supporting Information). Based on the crystal-
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Figure 4. Argon-adsorption isotherm of the calcined NUD-2. Insert: the pore-
size distribution curve based on DFT theory.
Figure 5. Solid-state 27Al NMR spectrum of NUD-2S-Al.
templates for zeolite synthesis. More importantly, the structure
of NUD-2 after the treatment remained intact (see Figure S6 in
the Supporting Information), whereas the germanium content
in the samples was significantly reduced; for example, Si/Ge=
8.8:1 in the as-synthesized NUD-2 increased to 50.6:1 after the
first treatment (Table 1). Repeated treatment further lowered
the germanium content, with the Si/Ge ratio reaching up to
210:1. The degermanated NUD-2 (denoted as NUD-2S) with
high Si/Ge ratios was stable after stirring in deionized water for
12 hours (see the XPRD images in Figure S6 in the Supporting
Information). It is noted that there were still relatively high
concentrations of germanium ions left in the as-made sample
with a low Si/Ge ratio of 2.12:1 after two treatments, likely be-
cause the germanium ions in these samples reside both in the
D4R units and in the layer; the latter are in stable configura-
tions and require further acid treatment to obtain water-stable
zeolites with high Si/Ge ratios.[19] Solid-state 29Si NMR spectra
of NUD-2S showed the peaks for the framework tetrahedral sil-
icon atoms between d=À95 and À120 ppm (see Figure S7 in
the Supporting Information), which are similar to the as-syn-
thesized NUD-2 and confirm the stability of NUD-2S. The nitro-
gen adsorption of the calcined NUD-2S gave a BET surface area
(denoted as NUD-2S-Al; Figure 5) showed a strong signal at
d=51.9 ppm and a small peak at d=À0.78 ppm (integal
ratio=16.8:1), which are due to the tetrahedrally and octahe-
drally coordinated species, respectively. These results suggest
that most of the aluminum ions are located in framework posi-
tions. Ammonia temperature-programmed desorption (NH3-
TPD) measurements of NUD-2S-Al showed strong desorption
peaks in the range 180–2508C and weak peaks at 280–3308C
(see Figure S8 in the Supporting Information), which are attrib-
uted to ammonia chemisorbed at weak and medium acid sites,
respectively. In contrast, NUD-2S did not exhibit any significant
acidity.
Finally, we note that NUD-2 is another new extra-large-pore
zeolite synthesized by using the SAT approach. Although the
organic cations in the as-synthesized NUD-2 were not located
in the single-crystal structure model due to disorder, the super-
molecular assemblies of OSDAs in NUD-2 can be confirmed by
means of photoluminescent studies. A dilute solution with the
monomer 1-methyl-3-(3’-methylbenzyl)imidazolium (SDA2)
weakly emitted at l=285 nm upon excitation at l=275 nm
(Figure 6). However, both the concentrated solution of SDA2
and the as-synthesized NUD-2 in solid gave an emission at l=
450 nm (lex =340 nm), which can be attributed to the forma-
tion of excimers. The results suggest that the aromatic-contain-
ing cations SDA2 formed self-assembled supermolecular ag-
gregates, likely through p–p interactions, during the zeolite
synthesis and acted as actual SDAs for the formation of NUD-2.
Similar phenomena were observed during the synthesis of ger-
of 369 m2 gÀ1 with
a t-plot micropore surface area of
329 cm3 gÀ1 and a micropore volume of 0.17 cm3 gÀ1 (see Fig-
ure S4 in the Supporting Information). Moreover, the aluminum
ions, which can generate acidic sites for potential catalytic ap-
plications, can be incorporated into the framework of NUD-2
through postsynthetic modification. The 27Al magic-angle spin-
ning (MAS) NMR spectrum of the aluminum-containing NUD-2
Table 1. Chemical composition and structural properties of as-made and treated NUD-2 zeolites.
SDA/Si in gel Ge/Si in gel Yield [%][a] Si/Ge in NUD-2 Si/Ge in NUD-2S treated once Si/Ge in NUD-2S treated twice Stability in water for 12h[b]
1.5
0.75
1.0
1.0
1.0
0.1
0.1
0.2
0.2
0.5
68
64
50
52
66
8.62
8.81
4.60
4.54
2.12
48.9
50.6
20.5
21.8
5.3
196
210
76.4
82.2
8.6
stable
stable
stable
stable
unstable
[a] Based on the Si(Ge) ions. [b] Determined by XPRD.
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state NMR spectra were recorded on a Bruker Av-400 spectrometer
by using the magic-angle spinning (MAS) technique at room tem-
perature. Solid-state 19F NMR spectroscopic analysis was carried out
at 376.47 MHz in zirconia rotors (diameter=4.0 mm) at a spinning
rate of 14 kHz and the spectra were collected with pulses of 2.1 ms,
which correspond to a magnetization flip angle of p/2rad and a re-
cycle delay of 10 s. The spectra were referenced to CFCl3. The
13C NMR spectra were acquired at a resonance frequency of
100.62 MHz by using a cross-polarization (CP) MAS sequence with
1
a H NMR excitation pulse of 3.0 ms, contact time of 2.0 ms, a recy-
cle delay of 5 s, and a spectral width of 100 kHz with proton de-
coupling at 60 kHz spinal64 during acquisition. The 29Si MAS NMR
spectra were acquired at a resonance frequency of 79.49 MHz with
a p/8 pulse at 56 kHz, spectral width of 100 kHz, and a relaxation
delay of 20 s. Solid-state 27Al NMR spectra were recorded on
a Varian Unity VXR-400WB spectrometer at 104.2 MHz, with a pulse
length of p/18rad, a recycle delay of 0.5 s, and a spinning rate of
14 kHz. The NH3 temperature-programmed desorption (NH3-TPD)
measurements were performed on a micromeritics AutoChem II
2920 chemisorption analyzer. The samples were first treated at
5508C in an air flow of 50 mLminÀ1 for 2 h and then cooled to
room temperature, exposed to NH3 at 1008C for 90 min, and
purged with helium at 508C for 5 h to eliminate the physically ad-
sorbed ammonia. Temperature-programmed desorption was con-
Figure 6. Photoluminescence spectra of the a) dilute (1ꢀ10À4 molLÀ1
,
lex =275 nm) and b) concentrated (0.3 molLÀ1, lex =340 nm) aqueous solu-
tion of SDA2OH. c) Solid-state photoluminescent spectrum of the as-synthe-
sized SDA2-NUD-2 (lex =340 nm).
manosilicates ITQ-29,[20] NUD-1,[16] and ITQ-37[22] and alumino-
phosphates LTA and AlPO-5.[21] These results show that the SAT
strategy is a general and facile approach to synthesize large-
and extra-large-pore zeolites.
ducted by ramping to 4508C at 108CminÀ1
.
The diffraction-data collection for single-crystal X-ray diffraction
studies of NUD-2 were carried out on the D8 Venture with Turbo
X-ray source with CuKa radiation (l=1.54178 ꢂ) at 296 K, with an
exposure time of 30 s in a shutterless mode. The detector distance
was 50 mm and the scan width was 0.58. Data reduction and ab-
sorption corrections were performed by using the SAINT and
SADABS programs, respectively. The structure was solved by using
direct methods with the SHELEX-2014 program and refined with
full-matrix least squares on F2 by using the SHELEX-2014 program.
All the organic cations and solvent molecular were not taken into
account and squeezed out by PLATON/SQUEEZE. The organic cat-
ions were confirmed by elemental analysis and TG measurements.
The non-hydrogen ions were refined anisotropically. There were
disorders at O10 and O11 in the layer and T3, T4, O7, O8, O9, and F
in the whole D4R unit, with each position taking half the occupan-
cies. Details of the crystal parameters, data collection, and refine-
ment results are summarized in Table S2 (see the Supporting Infor-
mation). The ionic-coordinate data and selected bond lengths and
angles are shown in Tables S3–S5, respectively (see the Supporting
Information).
Conclusion
A new extra-large-pore germanosilicate zeolite NUD-2 has
been synthesized by using a supramolecular-assembly-templat-
ing (SAT) approach. The NUD-2 network is built on two-dimen-
sional sheets and D4R units, thus forming a two-dimensional
interconnecting 14R and 10R channel system. The germanium
ions in NUD-2 can be replaced by silicon or aluminum through
postsynthetic modification to yield highly stable siliceous or
aluminosilicate zeolites. The successful synthesis of NUD-2 has
demonstrated that the SAT approach is a general and applica-
ble strategy that has great potential in the synthesis of new
large- and extra-large-pore zeolites.
Experimental Section
Crystal data for NUD-2: Ge4Si28O64(C12N2H15F)2.2
, Mr =2554.65,
platelike crystal, 0.070ꢀ0.025ꢀ0.005 mm3, orthorhombic, space
Materials and methods
group C222, a=13.7618(14), b=27.452(4), c=5.1170(5) ꢂ, a=b=
X-ray powder diffraction (XRPD) data were collected on a Bruker
D8 Advance instrument with CuKa radiation (l=1.54178 ꢂ) at
40 kV and 40 mA with a scanning speed of 0.1 minÀ1 in the 2q
range 5–508. Elemental analyses of C, H, and N were performed on
an Elemental Vario Micro elemental analyzer. Inductively coupled
plasma (ICP) analyses were carried out on a PerkinElmer Optima
3000DV. Thermogravimetric (TG) analyses were performed on a Per-
g=908, V=1933.2(4) ꢂ3, Z=1, 1calcd =2.194 gcm3,
F000 =1274,
6717 reflections collected, 1708 unique, (Rint =0.0773), final GooF=
1.092, R1 =0.0733, wR2 =0.1812. CCDC 1474068 contains the sup-
plementary crystallographic data for this paper. These data can be
obtained free of charge from The Cambridge Crystallographic
Data Centre.
kinElmer thermal analyzer in air with a heating rate of 5 KminÀ1
.
The Micrometrics ASAP 2020 surface-area porosimetry system was
used to measure N2 or Ar gas adsorption at 77 or 87 K. SEM/
energy-dispersive spectrometry (EDS) images were obtained on
a field-emission scanning electron microanalyzer (Hitachi S-4800)
by employing an accelerating voltage of 10 kV. Fluorescence meas-
urements were performed on a FluoroMax-4 spectrofluorometer
with slit of 3 nm for excitation and emission. Liquid-state 13C NMR
spectra were recorded on a Bruker DRX-500 spectrometer. Solid-
Synthesis of SDAs
1-Methyl-3-(2’-methylbenzyl)imidazolium chloride (SDA1Cl): 1-
Methyl-3H-imidazole (8.21 g, 100 mmol) was added to a solution of
2-methylbenzyl chloride (14.00 g, 100 mmol) dissolved in THF
(120 mL). The mixture was stirred at 343 K for 2 days. The solvent
was removed to yield a viscous oil, which was washed with ethyl
ether (3ꢀ10 mL) and dried under vacuum overnight (yield=92%).
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[3] Ch. Baerlocher, L. B. McCusker, D. H. Olson, Atlas of Zeolite Framework
Types, 6th ed., 2007, Elsevier, Amsterdam. http://www.iza-structure.org/
databases/.
[4] J. Jiang, J. Yu, A. Corma, Angew. Chem. Int. Ed. 2010, 49, 3120–3145;
Angew. Chem. 2010, 122, 3186–3212.
[5] J. Li, A. Corma, J. Yu, Chem. Soc. Rev. 2015, 44, 7112–7127.
[6] M. Moliner, F. Rey, A. Corma, Angew. Chem. Int. Ed. 2013, 52, 13880–
13889; Angew. Chem. 2013, 125, 14124–14134.
[7] G. Bellussi, A. Carati, C. Rizzo, R. Millini, Catal. Sci. Technol. 2013, 3, 833–
857.
The oil was dissolved in water (150 mL) and the chloride organic
salt SDA1Cl was converted into the corresponding hydroxide solu-
tion by anion exchange. Titration with aqueous HCl (0.1 molLÀ1) to
determine the final concentration of the hydroxide solution of
SDA1OH.
1-Methyl-3-(3’-methylbenzyl)imidazolium cholride (SDA2Cl): A
similar procedure was used that started from 3-methylbenzyl chlo-
ride to obtain SDA2Cl (yield=94%).
[8] R. F. Lobo, M. Tsapatsis, C. C. Freyhardt, S. Khodabandeh, P. Wagner, C.-Y.
Chen, K. J. Balkus, S. I. Zones, M. E. Davis, J. Am. Chem. Soc. 1997, 119,
8474–8484.
[9] P. Wagner, M. Yoshikawa, K. Tsuji, M. E. Davis, P. Wagner, M. Lovallo, M.
Taspatsis, Chem. Commun. 1997, 2179–2180.
[10] S. Smeets, D. Xie, C. Baerlocher, L. B. McCusker, W. Wan, X. Zou, S. I.
Zones, Angew. Chem. Int. Ed. 2014, 53, 10398–10402; Angew. Chem.
2014, 126, 10566–10570.
[11] A. Cheetham, H. Fjellvg, T. Gier, K. Kongshaug, K. Lillerud, G. Stucky,
Stud. Surf. Sci. Catal. 2001, 135, 158.
[12] A. Burton, S. Elomari, C. Y. Chen, R. C. Medrud, I. Y. Chan, L. M. Bull, C.
Kibby, T. V. Harris, S. I. Zones, E. S. Vittoratos, Chem. Eur. J. 2003, 9,
5737–5748.
[13] K. G. Strohmaier, D. E. Vaughan, J. Am. Chem. Soc. 2003, 125, 16035–
16039.
[14] J.-L. Paillaud, B. Harbuzaru, J. Patarin, N. Bats, Science 2004, 304, 990–
992.
[15] C. Jo, S. Lee, S. J. Cho, R. Ryoo, Angew. Chem. Int. Ed. 2015, 54, 12805–
12808; Angew. Chem. 2015, 127, 12996–12999.
Synthesis of zeolites
Zeolite NUD-2 was prepared from the gel with a molar composi-
tion of SiO2/xGeO2/ySDAOH/yHF/zH2O, where x=1–0.04, y=1–0.5,
and z=3–30 at 423 K for 15 days. A typical synthetic procedure
was as follows: germanium dioxide was added to a solution of
SDAOH and stirred for 30 min to be dissolved. Tetraethylorthosili-
cate was hydrolyzed in the above solution. The reaction mixture
was mechanically stirred at room temperature for about 2 h, and
then a solution of HF (40 wt%) was added. The mixture was homo-
genized and allowed to reach the desired water ratio by evapora-
tion of ethanol and some water at 808C. Finally, the gel was trans-
ferred into a steel autoclave with a Teflon-lined vessel (25 mL) and
heated at 423 K under static conditions for 15 days. The final
powder was filtered, washed with distilled water and ethanol, and
dried in air. Table S1 lists the various synthetic parameters that we
surveyed when using the designed SDA.
[16] F.-J. Chen, Y. Xu, H.-B. Du, Angew. Chem. Int. Ed. 2014, 53, 9592–9596;
Angew. Chem. 2014, 126, 9746–9750.
[17] J. Su, Y. Wang, J. Lin, J. Liang, J. Sun, X. Zou, Dalton Trans. 2013, 42,
1360–1363.
Degermanation of NUD-2
The as-synthesized SDA2-NUD-2 was dispersed in 12m HCl at
room temperature. Tetraethylorthosilicate was this added as a solu-
tion was added to the mixture by adding 0.020 mL per 0.1 g of
zeolite with stirring for 0.5 h. The mixture was transferred into
a Teflon-lined autoclave and heated at 443 K for 24 h. The final
powder was filtered and washed with deionized water and acetone
(2ꢀ). The process was repeated to obtain degermanated NUD-2S.
[18] a) J. Jiang, J. L. Jorda, M. J. Diaz-Cabanas, J. Yu, A. Corma, Angew. Chem.
Int. Ed. 2010, 49, 4986–4988; Angew. Chem. 2010, 122, 5106–5108; b) J.
Jiang, Y. Yun, X. Zou, J. L. Jorda, A. Corma, Chem. Sci. 2015, 6, 480–485;
c) A. Corma, M. J. Diaz-Cabanas, J. L. Jorda, C. Martinez, M. Moliner,
Nature 2006, 443, 842–845; d) J. Sun, C. Bonneau, A. Cantin, A. Corma,
M. J. Diaz-Cabanas, M. Moliner, D. Zhang, M. Li, X. Zou, Nature 2009,
458, 1154–1157; e) A. Corma, M. Dꢃaz-CabaÇas, J. Jiang, M. Afeworki, D.
Dorset, S. Soled, K. Strohmaier, Proc. Natl. Acad. Sci. USA 2010, 107,
13997–14002; f) R. Martꢃnez-Franco, M. Moliner, Y. Yun, J. Sun, W. Wan,
X. Zou, A. Corma, Proc. Natl. Acad. Sci. USA 2013, 110, 3749–3754; g) J.
Jiang, J. L. Jorda, J. Yu, L. A. Baumes, E. Mugnaioli, M. J. Diaz-Cabanas, U.
Kolb, A. Corma, Science 2011, 333, 1131–1134.
[19] a) H. Xu, J.-G. Jiang, B. Yang, L. Zhang, M. He, P. Wu, Angew. Chem. Int.
Ed. 2014, 53, 1355–1359; Angew. Chem. 2014, 126, 1379–1383; b) L.
Burel, N. Kasian, A. Tuel, Angew. Chem. Int. Ed. 2014, 53, 1360–1363;
Angew. Chem. 2014, 126, 1384–1387; c) F. Gao, M. Jaber, K. Bozhilov, A.
Vicente, C. Fernandez, V. Valtchev, J. Am. Chem. Soc. 2009, 131, 16580–
16586.
Alumination of NUD-2
NUD-2S was dispersed in 0.01m HCl at 363 K. Aluminum sulfate,
which was used as the aluminum source, was added to the mix-
ture by adding 15 mg per 0.1 g of zeolite with stirring overnight.
The final powder was filtered and washed with deionized water
until no aluminum ions were observed with the use of ammonium
auritricarboxylate (ATA). The final product was calcined at 823 K to
obtain NUD-2S-Al.
[20] A. Corma, F. Rey, J. Rius, M. J. Sabater, S. Valencia, Nature 2004, 431,
287–290.
Acknowledgments
[21] a) T. ꢄlvaro-MuÇoz, F. Lꢅpez-Arbeloa, J. Pꢆrez-Pariente, L. Gꢅmez-Horti-
gꢇela, J. Phys. Chem. C 2014, 118, 3069–3077; b) L. Gꢅmez-Hortigꢇela,
S. Hamad, F. Lꢅpez-Arbeloa, A. B. Pinar, J. Pꢆrez-Pariente, F. Corꢈ, J. Am.
Chem. Soc. 2009, 131, 16509–16524; c) L. Gꢅmez-Hortigꢇela, F. Lꢅpez-
Arbeloa, F. Corꢈ, J. Pꢆrez-Pariente, J. Am. Chem. Soc. 2008, 130, 13274–
13284.
[22] F.-J. Chen, Z.-H. Gao, L.-L. Liang, J. Zhang, H.-B. Du, CrystEngComm
2016, 18, 2735–2741.
[23] B. W. Boal, M. W. Deem, D. Xie, J. H. Kang, M. E. Davis, S. I. Zones, Chem.
Mater. 2016, 28, 2158–2164.
We are grateful for financial support from the National Natural
Science Foundation of China (21071075and 21471075) and the
Natural Science Foundation of the Higher Education Institu-
tions of Anhui Province, China (KJ2016A462). The authors
thank Mr Xiaokang Ke at Nanjing University for the solid-state
NMR spectroscopic measurements.
[24] A. Corma, M. J. Diaz-Cabanas, F. Rey, S. Nicolopoulus, K. Boulahya,
Chem. Commun. 2004, 1356–1357.
[25] J. P. Olivier, J. Porous Mater. 1995, 2, 9–17.
Keywords: germanium · silicates · structure elucidation ·
synthesis design · zeolites
[1] H. Du, C. Fairbridge, H. Yang, Z. Ring, Appl. Catal. A 2005, 294, 1–21.
[2] A. Corma, S. Iborra, A. Velty, Chem. Rev. 2007, 107, 2411–2502.
Received: May 20, 2016
Published online on && &&, 0000
&
&
Chem. Eur. J. 2016, 22, 1 – 7
www.chemeurj.org
6
ꢁ 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
ÝÝ These are not the final page numbers!

Full Paper
FULL PAPER
Ever expanding: A new extra-large-
pore germanosilicate NUD-2 was syn-
thesized by using a supramolecular-as-
sembly templating approach. This struc-
ture possesses a two-dimensional inter-
connecting 14- and 10-membered-ring
channel system (see figure). The germa-
nium centers in NUD-2 can be replaced
by silicon or aluminum atoms by means
of postsynthetic modification, thus
yielding highly stable siliceous or alumi-
nosilicate zeolites.
&
Microporous Materials
Z.-H. Gao, F.-J. Chen, L. Xu, L. Sun, Y. Xu,*
H.-B. Du*
&& – &&
A Stable Extra-Large-Pore Zeolite with
Intersecting 14- and 10-Membered-
Ring Channels
Chem. Eur. J. 2016, 22, 1 – 7
www.chemeurj.org
7
ꢁ 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
&
&
These are not the final page numbers! ÞÞ