Pillar-Assisted Construction of a Three-Dimensional Framework from a

Subscriber access provided by READING UNIV

Article

Pillar-assisted construction of 3D framework from 2D bilayer based on Zn/Cd hetero-metal cluster: pore tuning and gas adsorption danhua song, haiyang hou, Yu-Jie Gao, Feilong Jiang, Daqiang Yuan, Qihui Chen, Linfeng Liang, dong wu, and Maochun Hong Cryst. Growth Des., Just Accepted Manuscript • DOI: 10.1021/acs.cgd.7b01694 • Publication Date (Web): 01 Feb 2018 Downloaded from http://pubs.acs.org on February 2, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

Crystal Growth & Design is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

1

Pillar-assisted construction of 3D framework from 2D bilayer based on Zn/Cd

2

hetero-metal cluster: pore tuning and gas adsorption

3

4

Danhua Song,a, b Haiyang Hou, a, b Yu-Jie Gao, a, b Feilong Jiang,b Daqiang Yuan, b

5

Qihui Chen,*a, b Linfeng Liang, b Dong Wu,b and Maochun Hong* a, b

6

a

College of Chemistry, Fuzhou University, Fuzhou, 350002, China

7

b

Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, State Key

8

Laboratory of Structure Chemistry, Fujian Institute of Research on the Structure of

9

Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, China

10

Abstract

11 12

Employing rational design strategy to construct porous MOFs with predictable

13

structures for specific application still remains one of the most compelling challenges.

14

Here, a novel 2D bilayer (FJI-H16) based on Zn/Cd hetero-metal clusters has been

15

constructed throughout hetero-metal strategy, further introducing pillar ligands with

16

different sizes and flexibility expand such 2D bilayer structure into two novel 3D

17

frameworks (FJI-H17, FJI-H18), in which both of pore sizes and flexibility of the

18

new-formed 3D frameworks can be tuned. Further gas adsorption researches indicate

19

that the less porous FJI-H16 has highest H2 adsorption while the much porous

20

FJI-H17 has highest CO2 adsorption. The relationship between gas adsorption

21

properties and pore characteristics also has been investigated, which will provide a

22

potential strategy that can improve the gas adsorption in designing porous MOFs.

23 24

Keyword: metal-organic framework, 2D bilayer, hetero-metal clusters, pore tuning,

25

gas adsorption

ACS Paragon Plus Environment

Crystal Growth & Design 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 19

1

Introduction

2

Metal-organic frameworks (MOFs), which are crystalline solids constructed via

3

self-assembly of single metal cation or metal clusters and organic ligands having

4

multiple binding sites, have been researched extensively not only due to their

5

fascinating structures but also the potential applications in gas storage, separation and

6

catalyses and so on.1-12 Generally speaking, these functions mainly depend on the pore

7

characteristics of MOFs, including pore sizes, the window metrics. For example,

8

introduction of specific functional group into MOFs will lead to corresponding

9

properties;

13-16

introduction of specific templates or tuning pores can improve

10

adsorption capacity and selectivity.17-22 Thus, the design of MOF structure with

11

predictable pore characteristic is highly critical for the synthesis of MOFs material

12

with desired properties. However, employing rational design strategy to construct

13

predictable porous MOFs still remains one of the most compelling challenges for

14

chemists.

15

To achieve MOFs with tunable pore sizes from micro-pore to meso-pore,

16

various strategies have been used23,24 and pillar-assisted strategy that employing

17

different organic linkers to systematically change size of pore has been proved as an

18

effective route to controllably prepare porous MOF materials.22,25-41 By this way, the

19

pore structures of a wide variety of MOFs can be predicted and tuned. However, to

20

the best of our knowledge, almost of pillared-layer MOFs are assembled from

21

traditional paddle-wheel M2(RCOO)4 metal clusters, so new Secondary building units

22

(SBUs) for construction of pillared-layer MOFs should be designed and synthesized.

23

Here in, a novel 2D bilayer (FJI-H16) based on Zn/Cd hetero-metal clusters has been

24

constructed throughout hetero-metal strategy, further introducing pillar ligands with

25

different sizes and flexibility expand such 2D bilayer structure into two novel 3D

26

frameworks (FJI-H17, FJI-H18), in which both of

27

new-formed 3D frameworks can be tuned. Further gas adsorption researches indicate

28

that the less porous FJI-H16 has highest H2 adsorption while the much porous

29

FJI-H17 has highest CO2 adsorption. The relationship between gas adsorption

pore sizes and flexibility of the


Page 3 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1

properties and pore characteristics including size, chemical character, and flexibility

2

also has been investigated.

3

Experimental Section

4

General Procedures and Materials. All chemicals and solvents used were purchased

5

from commercial sources and used without further purification. The C, H, and N

6

micro analyses were performed using an Elementar Vario MICRO elemental analyzer.

7

The power X-ray diffraction (PXRD) data were collected on a Cu-Ka radiation

8

equipped RIGAKU DMAX 2500 diffractometer at room temperature. Thermal

9

gravimetric analyzer-mass spectrometry (TG-MS) was performed on a Netzsch STA

10

449C instrument and a Balzers MID instrument heated from room temperature to

11

1000 oC under a nitrogen atmosphere. Gas Sorption Measurements were measured on

12

a Micromeritics ASAP 2020 surface area analyzer.

13

Synthesis of FJI-H16. Dissolving Zn(NO3)2·6H2O (0.10 mmol, 30 mg),

14

Cd(NO3)2·4H2O (0.1 mmol, 30 mg) with ligand H3BTB (0.05 mmol, 22 mg) in a

15

mixture of 4mL DEF and 6mL ethanol solvent, then heating this solution at 85℃ for

16

4 days, after that, colorless rod-shaped crystals of FJI-H16 were obtained in a yield of

17

66%. Anal. calcd for [Zn2Cd(BTB)2(H2O)2]·0.5DEF·4H2O: C, 53.28; H, 3.84; N, 0.55.

18

Found: C, 52.90; H, 3.82; N, 0.61. FT-IR (KBr pellets, cm

19

1451, 1387, 1264, 1213, 1108, 1018, 847, 779, 702, 484.

20

Synthesis of FJI-H17. Dissolving H3BTB (0.05 mmol, 22 mg) 、Zn(NO3)2·6H2O

21

(0.10 mmol, 30 mg)、Cd(NO3)2·4H2O (0.10 mmol,30 mg) and BPY(0.1 mmol, 16 mg)

22

in 6mL DMA and 3mL H2O, then heating this solution at 85℃ for 4 days, after that,

23

colorless crystals of FJI-H17 were prepared in a yield of 66%. Anal. calcd for for

24

[Zn2Cd(BPY)(BTB)2]·3H2O·3DMA: C, 57.53; H, 4.57; N, 4.41. Found: C, 57.73; H,

25

4.41; N, 4.61. FT-IR (KBr pellets, cm−1): 1705, 1602, 1547, 1384, 1180, 1015, 860,

26

784, 706, 550, 471.

27

Synthesis of FJI-H18. Dissolving H3BTB (0.05 mmol, 22 mg) 、Zn(NO3)2·6H2O


−1

): 1662, 1598, 1551,


Page 4 of 19

1

(0.10 mmol, 30 mg)、Cd(NO3)2·4H2O (0.10 mmol,30 mg) and BPE (0.1 mmol, 18 mg)

2

in 6mL DMA and 3mL H2O, then heating this solution at 85℃ for 4 days, after that,

3

colorless crystals of FJI-H18 were synthesized in a yield of 62%. Anal. calcd for

4

[Zn2Cd(BPE)(BTB)2]·(2DMA·5H2O): C, 56.92; H, 4.45; N, 3.59. Found: C, 56.58; H,

5

4.20; N, 4.06. FT-IR (KBr pellets, cm−1): 1611, 1551, 1389, 1182, 1015, 855, 811, 782,

6

704, 550, 475.

7

X-ray crystallography. Data collections were all performed on a Mercury CCD

8

diffractometer with graphite monochromated CuKa radiation (λ = 0.71073 Å). The

9

structures were solved by direct methods, and all calculations were performed using

10

the SHELXL package. The structures FJI-H16-18 were refined by full matrix

11

least-squares with anisotropic displacement parameters for non-hydrogen atoms. All

12

hydrogen atoms were generated geometrically and treated as riding. The

13

crystallographic data are summarized in Table S1. CCDC numbers (1588923-1588925)

14

contain the supplementary crystallographic data for FJI-H16-18. These data can be

15

obtained free of charge from The Cambridge Crystallographic Data Centre via

16

www.ccdc.cam.ac.uk/data_request/cif.

17

Results and Discussion

18 19 20

In order to develop new SBU, Zn and Cd metal ions with different sizes but

21

similar coordination character have been selected as metal connectors, and H3BTB

22

has been selected as organic ligand due to its better directionality and rigidity (Figure

23

1a). Here in, a novel 2D bilayer structure (FJI-H16) based on Zn/Cd hetero-metal

24

cluster has been prepared. Reaction of Zn(NO3)2·6H2O, Cd(NO3)2·4H2O and ligand

25

H3BTB in a mixture of DEF and ethanol at 85℃ for 4 days affords rod-shaped

26

crystals

27

[Zn2Cd(BTB)2(H2O)2]·0.5DEF·4H2O. Single-crystal X-ray diffraction analyses reveal

28

the FJI-H16 crystallizes in the P63/mmc space group. Its asymmetric unit contains

of

FJI-H16

with

66%

yield


，

formulated

as

Page 5 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1

one sixth of independent Zn(II) ion, one third of independent Cd(II) ion, and one third

2

of deprotonated BTB ligand (Figure S1). Figure 1b illustrates the geometry of the

3

Zn/Cd hetero-metal cluster (Zn2Cd(COO)6(H2O)2). Each cadmium ion is chelated by

4

six Carboxylate oxygen atoms from six different BTB ligands with a distorted

5

octahedral geometry. Each of the two symmetry terminal Zn atoms is bound to three

6

carboxylate oxygen atoms from different BTB ligands and one oxygen atom from the

7

coordinated water with four-coordinate mode. The Zn-O bond distance ranges from

8

1.9305(12) to 1.966(3) Å and the Cd-O distance is 2.2828(12) Å. These Zn/Cd

9

hetero-metal clusters (Zn2Cd(COO)6(H2O)2) further link with BTB ligands to form an

10

infinite 2D bilayer structure (Figure 1c-d). Here in, BTB ligands comprised of bilayer

11

structure are parallel to each other with a distance of 3.524Å. These 2D bilayers

12

further stack into a 3D framework in the way of ABAB through π-π interaction (3.544

13

Å) (Figure 1e-f). PLATON calculation demonstrates that the solvent accessible

14

volume of FJI-H16 is 41.4%.

15

16



Page 6 of 19

1

Figure 1 The structure of FJI-H16. a) The structure of BTB ligand. b) The structure

2

of Zn/Cd hereto-metal cluster: Zn2Cd(COO)6(H2O)2.

3

viewed from different directions. e-f) The 3D framework viewed from different

4

directions. (Grey balls represent C atoms, red balls represent O atoms, yellow balls

5

represent Cd atoms, and cyan balls represent Zn atoms.)

c-d) The 2D bilayer structure

6 7

As mentioned above, almost of pillared-layer MOFs are assembled from traditional

8

paddle-wheel metal clusters M2(RCOO)4, such SBUs only lead to 2D single layer

9

structure. Here in, using the Zn/Cd hetero-metal clusters as SBUs can construct more

10

complex 2D bilayer structure, which will provide a new SBU for rational construction

11

of more diverse porous MOFs with predictable structures. (Scheme 2)

12

13 14

Scheme 1 The comparison between different 2D layer structures. a) The 2D single

15

layer structure based on traditional paddle-wheel metal clusters. b) The 2D bilayer

16

structure based on Zn/Cd hetero-metal clusters.


Page 7 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1

If the coordinated water comprised in Zn2Cd(COO)6(H2O)2 clusters (Figure 1b)

2

can be displaced by additional pillar ligands, such bilayer structure can further extend

3

into 3D framework driven by different pillar ligands as shown as Scheme 2a.

4

Therefore, a series of pyridine derivatives with different sizes from 2.8 Å to 11.1 Å,

5

including Pyrazine (2.8 Å), 4, 4'-Bipyridine (7.0 Å), trans-1,2-Bis(4-pyridyl)ethane

6

(9.3 Å),

7

have been tried as pillar ligands, and two novel 3D frameworks (FJI-H17 and

8

FJI-H18) based on 4, 4'-Bipyridine (BPY) and trans-1,2-Bis(4-pyridyl)ethane (BPE)

9

have been synthesized respectively. (Scheme 2)

1,2-Di(pyridin-4-yl)ethyne (9.6 Å), 1,4-Bis(pyrid-4-yl)benzene (11.1 Å),

10

11 12

Scheme 2 Construction of 3D frameworks driven by different pillar ligands.

13 14

Reaction of Zn(NO3)2·6H2O, Cd(NO3)2·4H2O, ligand H3BTB, auxiliary ligand



Page 8 of 19

1

BPY in a mixture of DMA and H2O at 85℃ for 4 days affords rod-shaped crystals of

2

FJI-H17, formulated as [Zn2Cd(BPY)(BTB)2]·3H2O·3DMA. X-ray diffraction

3

analyses indicate that FJI-H17 belongs to the monoclinic space group C2/c. Its

4

asymmetric unit contains an independent Zn(II) ion, half of independent Cd(II) ion, a

5

deprotonated BTB ligand, and half of BPY ligand (Figure S2). Figure 2a illustrates

6

the geometry of the new formed Zn/Cd hetero-metal cluster Zn2Cd(COO)6(BPY)2, in

7

which water molecules are displaced by pillar BPY ligands as we expected. Compared

8

with Zn2Cd(COO)6(H2O)2 clusters (Figure 1a), the Zn2Cd(COO)6(BPY)2 cluster has a

9

little distorted, each Cd atom is chelated by six carboxylate oxygen atoms from

10

different ligands with six-coordinate mode, while Zinc ion is chelated by three

11

carboxylate oxygen atoms from different ligands and a nitrogen atom from BPY

12

ligand with a four-coordinated mode. The Zn-O bond distance ranges from 1.931(3)

13

to 1.946(3) Å and the Cd-O distance ranges from 2.278(3) to 2.305(3) Å, and the

14

Zn-N distance is 2.034(4) Å. Such Zn2Cd(COO)6(BPY)2 clusters further link with

15

BTB ligands to form an a little twist infinite 2D bilayer structure with weaker π-π

16

interaction (3.865 Å) (Figure 2b). The pillar BPY ligands further link these 2D

17

bilayers into 3D framework as shown as Figure 3c with a distance of 7.0 Å. The

3D

18

structure

interpenetrates

with another

3D

19

two-fold

interpenetrated

structure, in which the intermolecular π-π distance

20

between two isolated 3D structure is 5.894 Å. Although FJI-H17 has a two-fold

21

interpenetrated structure, PLATON calculation demonstrates that the solvent

22

accessible volume of FJI-H17 is also up to 43.6%, a little larger than that of

23

FJI-H16.

one

to

24


give

access

to

a

Page 9 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1 2

Figure 2 The structure of FJI-H17. a) The structure of new-form Zn/Cd hereto-metal

3

cluster [Zn2Cd(COO)6(BPY)2]. (For clarity, only N atoms have been presented.) b)

4

The 2D bilayer structure based on [Zn2Cd(COO)6(BPY)2] clusters. c) The 3D

5

framework based on 2D bilayer structures. d) The two-fold intercatenated structure

6

based on 3D frameworks. (Grey balls represent C atoms, red balls represent O atoms,

7

yellow balls represent Cd atoms, and cyan balls represent Zn atoms.)

8

A similar 3D metal-organic framework (FJI-H18) is also obtained by

9

introducing BPE ligand to replace the coordinated H2O molecule of the original

10

Zn2Cd(COO)6(H2O) cluster. Reaction of Zn(NO3)2·6H2O, Cd(NO3)2·4H2O, ligand

11

H3BTB, auxiliary ligand BPE in a mixture of DMA and H2O at 85℃ for 4 days

12

affords

13

[Zn2Cd(BPE)(BTB)2]·(2DMA·5H2O). X-ray diffraction analyses indicate that

14

FJI-H18 belongs to the triclinic space group P-1. Its asymmetric unit contains two

15

independent Zn(II) ions, one independent Cd(II) ion, two deprotonated BTB ligands,

16

and one BPE ligand (Figure S3). Figure 3a illustrates the geometry of the new formed

rod-shaped

crystals

of

FJI-H18,


formulated

as


Page 10 of 19

1

Zn/Cd hetero-metal cluster Zn2Cd(COO)6(BPE)2, which is similar with that of

2

FJI-H17 except for more distorted. The Zn-O bond distance ranges from 1.9173(13)

3

to 1.9393(13) Å and the Cd-O distance ranges from 2.2747(13) to 2.3096(12) Å, and

4

the

5

Zn2Cd(COO)6(BPE)2 clusters further link with BTB ligands to form a more twist

6

infinite 2D bilayer structure with weak π-π interaction (3.785 Å) as shown as Figure

7

3b. The pillar BPE ligands further link these 2D bilayers into a 3D framework as

8

shown as Figure 3c with a distance of 9.3 Å. The 3D structure also interpenetrates

9

with another one to give access to a 3D two-fold interpenetrated structure (Figure 3d),

10

in which the intermolecular π-π distance between two isolated 3D structure is 8.397 Å.

11

PLATON calculation demonstrates that the solvent accessible volume of FJI-H18 is

12

51.5%, highly larger than that of FJI-H16 and FJI-H17.

Zn-N

distance

ranges

from

2.0250(17)

to

2.0284(16)

Å.

Such

13

14 15

Figure 3 The structure of FJI-H18. a) The structure of new-formed Zn/Cd


Page 11 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1

hereto-metal cluster Zn2Cd(COO)6(BPE)2. (For clarity, only N atoms have been

2

presented.)

3

framework based on 2D bilayer structures. d) The two-fold intercatenated structure

4

based on 3D frameworks. (Grey balls represent C atoms, red balls represent O atoms,

5

yellow balls represent Cd atoms, and cyan balls represent Zn atoms.)

b) The 2D bilayer structure based on Zn2Cd(COO)6(BPE)2. c) The 3D

6

Using hetero-metal strategy lead to a new Zn/Cd hetero-metal cluster comprised

7

in a novel 2D bilayer structure (FJI-H16); further driven by different pillar ligands,

8

another two 3D frameworks (FJI-H17-18) have been constructed as we expected.

9

Here in, attempts to directly obtain FJI-H17 and 18 based on crystals of FJI-H16 are

10

failed. After expanding by pillar ligands, both of FJI-H17 and FJI-H18 show larger

11

solvent accessible volumes even that both of them have two-fold interpenetrated

12

structures, and the FJI-H18 has the largest solvent accessible volume due to the

13

longer pillar ligand. Furthermore, introduction of pillar ligand also improve their

14

flexibility and reduce their structure symmetry.

15

To check the permanent porosities of FJI-H16, 17, 18, the freshly prepared

16

samples are soaked in ether to exchange the less volatile solvents, followed by

17

evacuation under a dynamic vacuum at 100 oC for 10 h, generating dehydrated forms.

18

PXRD data display that their crystallinity are finely kept after activation (Figure S5).

19

As shown in Figure 4, all of desolvated samples display typical type-I adsorption

20

isotherms, suggesting the retention of the micro-porous structures after the removal of

21

solvents from the crystalline samples. The adsorption tests show that the highest N2

22

adsorption capacity of the FJI-H16, 17, 18 is 193.0 cm3·g-1, 197.8cm3·g-1, 98.7

23

cm3·g-1

24

Brunauer-Emmett-Teller (BET) specific surface area is 684.2，774.9，345.5 m2g-1, and

25

the corresponding Langmuir specific surface area is 836.4, 841.7, 405.8 m2g-1

26

respectively.

27

than FJI-H16 and FJI-H17 even that it has larger solvent accessible volumes

28

calculated by PLATON, which may result from following factors: the pillared ligand

29

comprised in FJI-H18 is more flexible than FJI-H17, which will lead to possible

respectively.

By

model

calculation,

the

corresponding

The FJI-H18 shows significantly lower (BET) specific surface area



1

framework contraction, then N2 molecules is hardly to diffuse into its channels. After

2

expanding by pillar ligands, the pore sizes of both of new-formed 3D frameworks

3

(FJI-H17, 18) indeed enlarge. (Figure S6)

4 5

Figure 4 N2 adsorption isotherms of FJI-H16, 17, 18 at 77 K

6

H2 as an effective clean energy has attracted more and more attention, however,

7

the storage and transportation are still obstacles. MOFs which possess ordered pore

8

structures and high surface areas are considered to be effective candidates for storage

9

of H2.6 So we firstly investigate the hydrogen adsorption based on desolvated

10

FJI-H16, 17, 18. The H2 adsorption isotherms are carried out at 77 K, as shown as

11

Figure 5a-c, desolvated FJI-H16, 17, 18 exhibit the classical reversible type-I

12

isotherms for H2, and their total amount is 149.7 cm3 g−1 (1.34 wt%, 6.68 mmolg-1),

13

139.0 cm3 g−1 (1.24 wt%, 6.20 mmol g-1), and 77.7 cm3 g−1 (0.69 wt%, 3.45 mmol g-1)

14

respectively. FJI-H16 and FJI-H17showed a significantly larger H2 adsorption

15

capacity than FJI-H 18, and FJI-H16 is a little larger than FJI-H17. In addition, the

16

H2 adsorption value for FJI-H16 is also higher many famous reported metal organic

17

frameworks which have similar (BET) specific surface area as FJI-H16. 6 The higher

18

H2 adsorption for FJI-H16 may result from following two factors: 1) after activation,


Page 12 of 19

Page 13 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1

a large number of open metal sites of FJI-H16 will promote H2 adsorption; 2)

2

stronger π-π interactions comprised in FJI-H16 may improve the interaction between

3

H2 molecules and MOF framework (Table S2), The significantly lower H2 uptake for

4

FJI-H18 may also due to its possible framework contraction after activation.

5

6 7

Figure 5 H2 adsorption isotherms at 77K. a-c) represents FJI-H16, 17, 18

8

respectively.

9

Considering the rapid increase of CO2 emission, there is a constant need for

10

materials which can effectively eliminate CO2, and MOF materials have been proved

11

as cost-effective and efficient porous material for CO2 capture.2 So the measurements

12

on CO2 adsorption and selectivity against N2 based on desolvated FJI-H16, 17, 18

13

also have been carried out. The CO2 and N2 adsorption isotherms are carried out at

14

273 K. As shown as Figure 6a-c, desolvated FJI-H16, 17, 18 exhibit the classical



1

reversible type-I isotherms for CO2 and N2, and their total amount of CO2 uptake is

2

78.5 cm3 g-1 (3.50 mmol g-1, 154.2mg g-1), 92.0 cm3 g−1 (4.10 mmol g-1, 180.4mg g-1),

3

and 53.4 cm3 g−1 (2.37 mmol g-1, 104.28mg g-1) respectively at 273 K and 1 atm. By

4

the ideal adsorbed solution theory (IAST), the CO2/N2 selectivity of FJI-H16, 17, 18

5

for the 15/85 CO2/N2 mixture at 1 atm and 273 K is calculated to be 80, 79, and 60

6

respectively. The FJI-H17 shows a larger CO2 adsorption capacity than FJI-H16 and

7

FJI-H18 due to its much porous, which can be comparable with many famous

8

metal-organic porous compounds.2 All of three compounds display high CO2/N2

9

selectivity due to their ultra-microporous structures, in which the pore size

10

distribution of FJI-H16, 17, 18 are mainly focus on 5.9, 7.3, 6.8 Å respectively. Such

11

limited ultra-micropores prefer to allow passage of smaller CO2 molecules and

12

exclude larger N2 molecules.

13 14

Figure 6 The CO2 and N2 adsorption isotherms of FJI-H16, 17, 18 at 273 K. a-c)

15

represents FJI-H16, 17, 18 respectively. d) The CO2/N2 selectivity of FJI-H16, 17,

16

18 for the 15/85 CO2/N2 mixture at 1 atm and 273 K.


Page 14 of 19

Page 15 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Conclusions

1 2

In conclusion, employing rational design strategy in the construction of porous

3

MOFs with predictable structures for specific application still remains one of the most

4

compelling challenges for chemists. Here in, a novel 2D bilayer (FJI-H16) based on

5

Zn/Cd hetero-metal clusters has been constructed throughout hetreo-metal strategy,

6

introducing pillar ligands with different size and flexibility expand such bilayer

7

structure into another two much porous 3D frameworks (FJI-H17, FJI-H18), in

8

which the pore sizes have been enlarged and flexibility of frameworks have been

9

changed. Further researches indicate that the less porous FJI-H16 has highest H2

10

adsorption, while much porous FJI-H17 has highest CO2 adsorption. Such different

11

gas adsorption properties are due to their different pore characteristics including size,

12

chemical character, and flexibility, which will provide a potential strategy that can

13

improve the gas adsorption in designing porous MOFs.

14

ASSOCIATED CONTENT

15

Electronic Supplementary Information (ESI) available: Additional Crystallographic

16

data, Figures, TGA spectra and PXRD for FJI-H16-18. CCDC numbers

17

(1588923-1588925) contain the supplementary crystallographic data for FJI-H16-18.

18

AUTHOR INFORMATION

19

Corresponding Author

20

Maochun Hong

21

*E-mail: [email protected]

22

Qihui Chen

23

*E-mail: [email protected]

24

D. Song and H. Hou contributed equally to this work.

25

Notes ACS Paragon Plus Environment


Page 16 of 19

1

The authors declare no competing financial interest.

2

ACKNOWLEDGEMENTS

3

Dedicated to professor Xin-Tao Wu on the ocassion of his 80th birthday. This work

4

was supported by the "Strategic Priority Research Program" of the Chinese Academy

5

of Sciences (XDB20000000), the 973 Program (2014CB932101), National Natural

6

Science Foundation of China (21471148, 21731006, 21390392),

7

Innovation Promotion Association CAS.

and the Youth

8 9

References

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

(1) O’Keeffe, M.; Yaghi, O. M. Deconstructing the Crystal Structures of Metal–Organic Frameworks and Related Materials into Their Underlying Nets. Chem. Rev. 2012, 112, 675-702. (2) Sumida, K.; Rogow, D. L.; Mason, J. A.; McDonald, T. M.; Bloch, E. D.; Herm, Z. R.; Bae, T.-H.; Long, J. R. Carbon Dioxide Capture in Metal–Organic Frameworks. Chem. Rev. 2012, 112, 724-781. (3) Wu, H.; Gong, Q.; Olson, D. H.; Li, J. Commensurate Adsorption of Hydrocarbons and Alcohols in Microporous Metal Organic Frameworks. Chem. Rev. 2012, 112, 836-868. (4) Zhang, J.-P.; Zhang, Y.-B.; Lin, J.-B.; Chen, X.-M. Metal Azolate Frameworks: From Crystal Engineering to Functional Materials. Chem. Rev. 2012, 112, 1001-1033. (5) Cui, Y.; Yue, Y.; Qian, G.; Chen, B. Luminescent Functional Metal–Organic Frameworks. Chem. Rev. 2012, 112, 1126-1162. (6) Suh, M. P.; Park, H. J.; Prasad, T. K.; Lim, D.-W. Hydrogen Storage in Metal–Organic Frameworks. Chem. Rev. 2012, 112, 782-835. (7) Yan, Y.; Yang, S.; Blake, A. J.; Schröder, M. Studies on Metal–Organic Frameworks of Cu(II) with Isophthalate Linkers for Hydrogen Storage. Acc. Chem. Res. 2014, 47, 296-307. (8) Getman, R. B.; Bae, Y.-S.; Wilmer, C. E.; Snurr, R. Q. Review and Analysis of Molecular Simulations of Methane, Hydrogen, and Acetylene Storage in Metal–Organic Frameworks. Chem. Rev. 2012, 112, 703-723. (9) Ferey, G.; Serre, C. Large breathing effects in three-dimensional porous hybrid matter: facts, analyses, rules and consequences. Chem. Soc. Rev. 2009, 38, 1380-1399. (10) Liu, J.; Chen, L.; Cui, H.; Zhang, J.; Zhang, L.; Su, C.-Y. Applications of metal-organic frameworks in heterogeneous supramolecular catalysis. Chem. Soc. Rev. 2014, 43, 6011-6061. (11) Zhu, Q.-L.; Xu, Q. Metal-organic framework composites. Chem. Soc. Rev. 2014, 43, 5468-5512. (12) Gao, W. Y.; Chrzanowski, M.; Ma, S. Q. Metal-metalloporphyrin frameworks: a resurging class of functional materials. Chem. Soc. Rev. 2014, 43, 5841-5866.


Page 17 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

(13) Liang, L.; Liu, C.; Jiang, F.; Chen, Q.; Zhang, L.; Xue, H.; Jiang, H.-L.; Qian, J.; Yuan, D.; Hong, M. Carbon dioxide capture and conversion by an acid-base resistant metal-organic framework. Nat. Commun. 2017, 8, 1233. (14) Xue, H.; Chen, Q.; Jiang, F.; Yuan, D.; Lv, G.; Liang, L.; Liu, L.; Hong, M. A regenerative metal-organic framework for reversible uptake of Cd(ii): from effective adsorption to in situ detection. Chem. Sci. 2016, 7, 5983-5988 (15) Liang, L.; Chen, Q.; Jiang, F.; Yuan, D.; Qian, J.; Lv, G.; Xue, H.; Liu, L.; Jiang, H.-L.; Hong, M. In situ large-scale construction of sulfur-functionalized metal-organic framework and its efficient removal of Hg(ii) from water. J. Mater. Chem. A 2016, 4, 15370-15374. (16) Yee, K.-K.; Reimer, N.; Liu, J.; Cheng, S.-Y.; Yiu, S.-M.; Weber, J.; Stock, N.; Xu, Z. Effective Mercury Sorption by Thiol-Laced Metal–Organic Frameworks: in Strong Acid and the Vapor Phase. J. Am. Chem. Soc. 2013, 135, 7795-7798. (17) Chen, S.-S.; Wang, P.; Takamizawa, S.; Okamura, T.-a.; Chen, M.; Sun, W.-Y. Zinc(ii) and cadmium(ii) metal-organic frameworks with 4-imidazole containing tripodal ligand: sorption and anion exchange properties. Dalton Trans. 2014, 43, 6012-6020. (18) Cui, P.-P.; Zhang, X.-D.; Wang, P.; Zhao, Y.; Azam, M.; Al-Resayes, S. I.; Sun, W.-Y. Zinc(II) and Copper(II) Hybrid Frameworks via Metal-Ion Metathesis with Enhanced Gas Uptake and Photoluminescence Properties. Inorg. Chem. 2017, 56, 14157-14163. (19) Chen, K.-J.; Madden, D. G.; Pham, T.; Forrest, K. A.; Kumar, A.; Yang, Q.-Y.; Xue, W.; Space, B.; Perry, J. J.; Zhang, J.-P.; Chen, X.-M.; Zaworotko, M. J. Tuning Pore Size in Square-Lattice Coordination Networks for Size-Selective Sieving of CO2. Angew. Chem. Int. Ed. 2016, 55, 10268–10272. (20) Ban, Y. J.; Li, Z. J.; Li, Y. S.; Peng, Y.; Jin, H.; Jiao, W. M.; Guo, A.; Wang, P.; Yang, Q. Y.; Zhong, C. L.; Yang, W. S. Confinement of Ionic Liquids in Nanocages: Tailoring the Molecular Sieving Properties of ZIF-8 for Membrane-Based CO2 Capture. Angew. Chem. Int. Ed. 2015, 54, 15483-15487. (21) Nugent, P.; Belmabkhout, Y.; Burd, S. D.; Cairns, A. J.; Luebke, R.; Forrest, K.; Pham, T.; Ma, S. Q.; Space, B.; Wojtas, L.; Eddaoudi, M.; Zaworotko, M. J. Porous materials with optimal adsorption thermodynamics and kinetics for CO2 separation. Nature 2013, 495, 80-84. (22) Matsuda, R.; Tsujino, T.; Sato, H.; Kubota, Y.; Morishige, K.; Takata, M.; Kitagawa, S. Temperature responsive channel uniformity impacts on highly guest-selective adsorption in a porous coordination polymer. Chem. Sci. 2010, 1, 315-321. (23) Cai, G.; Jiang, H.-L. A Modulator-Induced Defect-Formation Strategy to Hierarchically Porous Metal–Organic Frameworks with High Stability. Ange. Chem. Int. Ed. 2017, 56, 563-567. (24) Ding, Y.; Chen, Y.-P.; Zhang, X.; Chen, L.; Dong, Z.; Jiang, H.-L.; Xu, H.; Zhou, H.-C. Controlled Intercalation and Chemical Exfoliation of Layered Metal–Organic Frameworks Using a Chemically Labile Intercalating Agent. J. Am. Chem. Soc. 2017, 139, 9136-9139. (25) Luo, X.-L.; Yin, Z.; Zeng, M.-H.; Kurmoo, M. The construction, structures, and functions of pillared layer metal-organic frameworks. Inorg. Chem. Front. 2016, 3, 1208-1226. (26) Zhang, Z.-X.; Ding, N.-N.; Zhang, W.-H.; Chen, J.-X.; Young, D. J.; Hor, T. S. A. Stitching 2D Polymeric Layers into Flexible Interpenetrated Metal–Organic Frameworks within Single Crystals. Angew. Chem. Int. Ed. 2014, 53, 4628-4632. (27) Wang, R.; Meng, Q.; Zhang, L.; Wang, H.; Dai, F.; Guo, W.; Zhao, L.; Sun, D. Investigation of the effect of pore size on gas uptake in two fsc metal-organic frameworks. Chem. Commun. 2014, 50, 4911-4914.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

(28) Meng, X.; Zhong, R.-L.; Song, X.-Z.; Song, S.-Y.; Hao, Z.-M.; Zhu, M.; Zhao, S.-N.; Zhang, H.-J. A stable, pillar-layer metal-organic framework containing uncoordinated carboxyl groups for separation of transition metal ions. Chem. Commun. 2014, 50, 6406-6408. (29) Hu, X.-L.; Liu, F.-H.; Wang, H.-N.; Qin, C.; Sun, C.-Y.; Su, Z.-M.; Liu, F.-C. Controllable synthesis of isoreticular pillared-layer MOFs: gas adsorption, iodine sorption and sensing small molecules. J. Mater. Chem. A 2014, 2, 14827-14834. (30) Dutta, A.; Wong-Foy, A. G.; Matzger, A. J. Coordination copolymerization of three carboxylate linkers into a pillared layer framework. Chem. Sci. 2014, 5, 3729-3734. (31) Schoedel, A.; Boyette, W.; Wojtas, L.; Eddaoudi, M.; Zaworotko, M. J. A Family of Porous Lonsdaleite-e Networks Obtained through Pillaring of Decorated Kagomé Lattice Sheets. J. Am. Chem. Soc. 2013, 135, 14016-14019. (32) He, Y.-P.; Tan, Y.-X.; Zhang, J. Tuning a layer to a pillared-layer metal-organic framework for adsorption and separation of light hydrocarbons. Chem. Commun. 2013, 49, 11323-11325. (33) Han, L.; Xu, L.-P.; Qin, L.; Zhao, W.-N.; Yan, X.-Z.; Yu, L. Syntheses, Crystal Structures, and Physical Properties of Two Noninterpenetrated Pillar-Layered Metal–Organic Frameworks Based on N,N′-Di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxydiimide Pillar. Cryst. Growth Des. 2013, 13, 4260-4267. (34) Mulfort, K. L.; Farha, O. K.; Stern, C. L.; Sarjeant, A. A.; Hupp, J. T. Post-Synthesis Alkoxide Formation Within Metal−Organic Framework Materials: A Strategy for Incorporating Highly Coordinatively Unsaturated Metal Ions. J. Am. Chem. Soc. 2009, 131, 3866-3868. (35) Chun, H.; Jung, H.; Seo, J. Isoreticular Metal-Organic Polyhedral Networks Based on 5-Connecting Paddlewheel Motifs. Inorg. Chem. 2009, 48, 2043-2047. (36) Choi, E.-Y.; Barron, P. M.; Novotny, R. W.; Son, H.-T.; Hu, C.; Choe, W. Pillared Porphyrin Homologous Series: Intergrowth in Metal−Organic Frameworks. Inorg. Chem. 2009, 48, 426-428. (37) Sun, J.; Zhou, Y.; Fang, Q.; Chen, Z.; Weng, L.; Zhu, G.; Qiu, S.; Zhao, D. Construction of 3D Layer-Pillared Homoligand Coordination Polymers from a 2D Layered Precursor. Inorg. Chem. 2006, 45, 8677-8684. (38) Chun, H.; Dybtsev, D. N.; Kim, H.; Kim, K. Synthesis, X-ray Crystal Structures, and Gas Sorption Properties of Pillared Square Grid Nets Based on Paddle-Wheel Motifs: Implications for Hydrogen Storage in Porous Materials. Chem. Eur. J. 2005, 11, 3521-3529. (39) Kitaura, R.; Iwahori, F.; Matsuda, R.; Kitagawa, S.; Kubota, Y.; Takata, M.; Kobayashi, T. C. Rational Design and Crystal Structure Determination of a 3-D Metal−Organic Jungle-Gym-like Open Framework. Inorg. Chem. 2004, 43, 6522-6524. (40) Dybtsev, D. N.; Chun, H.; Kim, K. Rigid and Flexible: A Highly Porous Metal–Organic Framework with Unusual Guest-Dependent Dynamic Behavior. Angew. Chem. Int. Ed. 2004, 43, 5033-5036. (41) Kondo, M.; Okubo, T.; Asami, A.; Noro, S.-i.; Yoshitomi, T.; Kitagawa, S.; Ishii, T.; Matsuzaka, H.; Seki, K. Rational Synthesis of Stable Channel-Like Cavities with Methane Gas Adsorption Properties: [{Cu2(pzdc)2(L)}n] (pzdc=pyrazine-2,3-dicarboxylate; L=a Pillar Ligand). Angew. Chem. Int. Ed. 1999, 38, 140-143.

41 42


Page 18 of 19

Page 19 of 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

"For Table of Contents Use Only" Pillar-assisted construction of 3D framework from 2D bilayer based on Zn/Cd hetero-metal cluster: pore tuning and gas adsorption Danhua Song, Haiyang Hou, Yu-Jie Gao, Feilong Jiang, Daqiang Yuan, Qihui Chen, * Linfeng Liang, Dong Wu, and Maochun Hong* TOC graphic

Synopsis Two novel three-dimensional frameworks with different pore sizes and flexibility have been constructed from a new-formed two-dimensional bilayer structure based on pillar-assisted strategy. Their pores characteristics and gas adsorption properties have been investigated, which will provide a potential strategy that can improve the gas adsorption in designing porous MOFs.


Pillar-Assisted Construction of a Three-Dimensional Framework from a

Recommend Documents