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Supporting Information

for

Pillar[n]arene-basedSupramolecularOrganicFrameworkswithHigh

HydrocarbonStorageandSelectivity

Li-Li Tan,§a,b Youlong Zhu,b Hai Long,c Yinghua Jin,b Wei Zhang,*b and Ying-Wei Yang*a

a International Joint Research Laboratory of Nano-Micro Architecture Chemistry (NMAC), College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China. E-mail: ywyang@jlu.edu.cn b Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. E-mail: wei.zhang@colorado.edu c National Renewable Energy Laboratory, Golden, CO 80401, USA. §Present address: State Key Laboratory of Solidification Processing, Center of Nano Energy Materials, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an, 710072, P.R. China.

Table of Contents

1. Materials and Methods

2. Gas Sorption

3. Isosteric Heat of Gas Adsorption

4. IAST Analysis of the Selectivity Data of Gas Adsorption

5. Crystal Structure Analysis

6. Binding sites calculation

Electronic Supplementary Material (ESI) for ChemComm.This journal is © The Royal Society of Chemistry 2017

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1. Materials and Methods

Starting materials were commercially available, and used as received. The Quantachrome

Autosorb ASiQ automated gas sorption analyzer was used to measure N2, H2, C2H2, C2H4,

C2H6 and CH4 adsorption isotherms. The sample was heated at 170 °C and kept at this

temperature for at least 24 hours under the vacuum for the activation. Ultra high purity grade

(99.999% purity) N2, H2, CH4, C2H2, C2H4, C2H6 and He, oil-free valves and gas regulators

were used for all free space corrections and measurements. For all the gas adsorption

measurements, the temperatures were controlled by using a refrigerated bath of liquid N2 (77

K), ice water (273 K) and room temperature (298 K).

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2. Gas Sorption

Figure S1. Isotherm adsorption at 298 K. a, P5-SOF. b, P6-SOF.

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3. Isosteric Heat of Gas Adsorption

To determine the binding affinity of pillar[n]arene-SOFs for different gases, we calculated the Qst for

different gases using the virial method based on two independent temperature gas adsorption isotherms. In

each case, the data were fitted using the following equation:

lnP = lnN +1𝑇

𝑎!𝑁! +!

!!!

𝑏!𝑁!!

!!!

Where P is pressure expressed in Pa; N is the adsorption capacity expressed in mmol/g; T is the absolute

temperature expressed in K; ai and bj are virial coefficients, m and n are the number of coefficients to

describe the adsorption isotherms, usually m ≤6 and n ≤3. The isosteric heat of adsorption is calculated

through the following expression:

𝑄!" = −R 𝑎!𝑁!!

!!!

Where R is universal gas constant. In this manuscript, Qst is based on the gas adsorption from 0 to 103.99

kPa.

3.1 Isosteric Heats of Gas Adsorption of P5-SOF

Figure S2. Virial analysis of C2H2, C2H4, C2H6, CH4, N2 and H2 adsorption isotherms of P5-SOF at 298 K (filled symbols) and 273 K (open symbols).

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Table S1. Virial equation fitting results of C2H2 adsorption of P5-SOF.

Table S2. Virial equation fitting results of C2H4 adsorption of P5-SOF.

Table S3. Virial equation fitting results of C2H6 adsorption of P5-SOF.

Table S4. Virial equation fitting results of CH4 adsorption of P5-SOF.

Table S5. Virial equation fitting results of H2 adsorption of P5-SOF.

Table S6. Virial equation fitting results of N2 adsorption of P5-SOF.

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-12039.78428 13612.70914 3539.74658 -11123.61093 4234.55121 -519.2477 52.31374 -65.53678 31.21317 0.997

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-8737.04529 19099.98362 -12940.79682 2754.93117 -2010.98311 756.41375 40.10663 -61.59084 36.86683 0.997

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-64.80825 6532.56368 -43140.29186 134976.23243 -208505.19955 124097.63656 10.56795 0.0682 4.37963 0.9993

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

551.90363 -12257.56954 17469.97165 -10342.65068 9653.83895 -3608.84593 10.13691 40.07679 -43.91852 0.99976

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-934.31922 62048.03306 -712304.07998 5.81977E6 -3.87599E7 7.52565E7 16.72777 -184.62094 1246.24297 0.998

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

2083.50608 -12095.33521 185131.98059 -2.18283E6 1.1978E7 -2.47941E7 6.41813 16.48985 0.02998 0.9997

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3.2 Isosteric Heats of Gas Adsorption of P6-SOF

Figure S3. Virial analysis of C2H2, C2H4, C2H6, CH4, N2 and H2 adsorption isotherms of P6-SOF at 298 K (filled symbols) and 273 K (open symbols).

Table S7. Virial equation fitting results of C2H2 adsorption of P6-SOF.

Table S8. Virial equation fitting results of C2H4 adsorption of P6-SOF.

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-2998.59018 -188.34551 -184.34283 -2847.94596 1253.50987 -117.19481 19.96163 -0.27228 9.87805 0.99989

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-2451.84586 7286.33192 48276.09708 -150211.13211 181598.5823 -78798.55493 17.8095 -42.61219 12.66803 0.99434

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Table S9. Virial equation fitting results of C2H6 adsorption of P6-SOF.

Table S10. Virial equation fitting results of CH4 adsorption of P6-SOF.

Table S11. Virial equation fitting results of H2 adsorption of P6-SOF.

Table S12. Virial equation fitting results of N2 adsorption of P6-SOF.

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-1060.90056 52629.38847 -265428.96384 853576.27618 -1.31929E6 772191.80514 8.43105 -52.11262 20.92596 0.99

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

-1368.60745 6407.37833 68841.50941 -475859.59215 1.08977E6 -914403.37903 17.4883 -48.38482 83.10875 0.99

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

2877.27754 -41621.38082 476262.5036 -3.51571E6 2.12533E7 -4.74315E7 4.07178 109.8892 -712.40048 0.99769

a0 a1 a2 a3 a4 a5 b0 b1 b2 R2

757.44898 6035.1346 33274.98361 -544169.68046 1.9725E6 -2.77273E6 10.84568 -35.72386 132.13018 0.9997

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4. IAST Analysis of the Selectivity Data of Gas Adsorption

Ideal adsorbed solution theory (IAST) was used to determine the selectivity factor, S, for binary mixtures

using pure component isotherm data. The selectivity factor, S, is defined according to the following

equation where xi is the amount of each component adsorbed as determined from IAST and yi is the mole

fraction of each component in the gas phase at equilibrium. The IAST adsorption selectivities were

calculated for binary mixtures of varying compositions at 273 K and 298 K with a total pressure of 1.0 bar.

S = (x1/y1)/(x2/y2)

4.1 P5-SOF

Figure S4. Experimental single component adsorption isotherms at 298 K and IAST prediction of adsorption from binary 50 mol % gas mixture on P5-SOF.

Figure S5. IAST adsorption selectivity calculated under the condition of a 50/50 gas mixture at 273 K. The selectivity of acetylene over H2 is higher than 10000.

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Figure S6. IAST adsorption selectivity calculated under the condition of a 50/50 gas mixture at 298 K. 4.2 P6-SOF

Figure S7. IAST adsorption selectivity calculated under the condition of a 50/50 gas mixture at 273 K.

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Figure S8. IAST adsorption selectivity calculated under the condition of a 50/50 gas mixture at 298 K.

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5. Crystal Structure Analysis

Figure S9. Pore structure and connectivity. The molecules are shown in stick models, and the lattice voids are depicted as green Connolly surfaces (probe radius = 1.2 Å, grid = 0.2 Å, the inside color of Connolly surface is yellow) a, P5-SOF. b, P6-SOF.

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6. Binding sites calculation

The possible binding sites of C2H2 and C2H4 in pillarene-based SOFs were obtained by the SCC-DFTB

calculations. Calculations on four different binding sites in P6-SOF, and three binding sites in P5-SOF were

carried out.

6.1. P5-SOF

P5-SOF has three most preferred binding sites, stabilized by C−H···O@C2H2, C−H···π@C2H2,

C−H···O@C2H4 and C−H···π@C2H4. The most stable configurations are characterized by strong

C−H···O@C2H2 (B.E. = −0.9784 kcal/mol, site II, between four P5 molecules) and C−H···O@C2H4 (B.E.

= −0.8427 kcal/mol, site II, between four P5 molecules) hydrogen bond interactions.

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Figure S10. Optimized stable configurations of the complex P5-SOF·C2H2. C, O and H are shown as dark gray, red and white spheres, respectively.

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Figure S11. Optimized stable configurations of the complex P5-SOF·C2H4. C, O and H are shown as dark gray, red and white spheres, respectively.

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6.2. P6-SOF

P6-SOF has four most preferred binding sites, stabilized by C−H···O@C2H2, π···π@C2H2,

C−H···O@C2H4 and π···π@C2H4. The most stable configurations are characterized by strong

C−H···O@C2H2 (B.E. = −1.701 kcal/mol, site II, between two P6 molecules) and C−H···O@C2H4 (B.E. =

−0.8494 kcal/mol, site IV, between six P6 molecules) hydrogen bond interactions.

Figure S12. Optimized stable configurations of the complex P6-SOF·C2H2. C, O and H are shown as dark gray, red and white spheres, respectively.

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Figure S13. Optimized stable configurations of the complex P6-SOF·C2H4. C, O and H are shown as dark gray, red and white spheres, respectively.