Local Deprotonation Enables Cation Exchange, Porosity. Modulation and Tunable Adsorption Selectivity in a. Metal-Organic Framework

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1 Supporting Information for Local Deprotonation Enables Cation Exchange, Porosity Modulation and Tunable Adsorption Selectivity in a Metal-Organic Framework Jun-Hao Wang,, Dong Luo, Mian Li, and Dan Li *,, Department of Chemistry, Shantou University, Guangdong , P. R. China College of Chemistry and Materials Science, Jinan University, Guangzhou , P. R. China Institute of Crystalline Materials, Shanxi University, Taiyuan , P. R. China

2 Cation Exchange Experiments was suspending in methanolic solution of ANO3 salts (A = Li +, Mg 2+ /2, La 3+ /3) (concentration, 0.1 M) or organic amines (Me3N, Et3N) (concentration, 0.5 M) for 8 days. All the exchanged solids were subsequently filtered, washed with MeOH for 3 times and later on suspended during 24 hours in MeOH. Afterwards, the materials were filtered again and washed with MeOH. The effect of ion exchange on the materials was examined by means of thermal analysis (Figure S1), IR (Figure S2), PXRD experiments (Figure 1 in the main text), atomic absorption, 1 H-NMR, and N2 adsorption at 77 K (Figure 4 in the main text). Atomic absorption results for A@ZnPzC materials: The atomic absorption results give rise to the following formulations: Li[Zn3(μ3-OH)(μ3-4-carboxypyrazolato)3], Mg0.5[Zn3(μ3-OH)(μ3-4-carboxypyrazolato )3], Tb0.33[Zn3(μ3-OH)(μ3-4-carboxypyrazolato)3], Eu0.33[Zn3(μ3-OH)(μ3-4-carboxypyr azolato)3], Tb0.17Eu0.16[Zn3(μ3-OH)(μ3-4-carboxypyrazolato)3]. 1 H-NMR results for A@ZnPzC materials: The 1 H-NMR results give rise to the following formulations: (Me3NH)0.3(NH4)0.7[Zn3(μ3-OH)(μ3-4-carboxypyrazolato)3], (Et3NH)0.85(NH4)0.15[Zn3(μ3-OH)(μ3-4-carboxypyrazolato)3]. In the 1 H-NMR analysis, the integration for one set of the pyrazole-4-carboxylic aromatic hydrogens was set as 6 (for the (Me3NH)0.3(NH4)0.7[Zn3(μ3-OH)(μ3-4-carboxypyrazolato)3] unit). We then integrated the methyl peak for each cation to determine the number of organic cations per material: (CH3)3NH + :δ2.78 (singlet, 2.74 H); (CH3CH2)3NH + :δ2.01 (triplet, 7.62 H). S1

3 Liquid-Phase Separation of Benzene/Cyclohexane materials were activated at 85 o C under vacuum for 24 hours and then were immersed into benzene/cyclohexane 1:1 mixtures for about 24 hours. Then the samples were acid-hydrolyzed by DCl in d6-dmso (100 μl DCl in 500 μl d6-dmso). 1 H-NMR (400 MHz) spectra of dissolved A@ZnPzC were collected at room temperature. The integration for cyclohexane was set as 12. We then integrated benzene to determine the adsorption selectivity of A@ZnPzC materials towards benzene over cyclohexane. For NH4@ZnPzC, Li@ZnPzC, Mg@ZnPzC and Tb@ZnPzC, only negligible amounts of benzene and cyclohexane were detected. For Me3NH@ZnPzC: benzene,δ7.37 (singlet, 18 H); cyclohexane,δ1.40 (singlet, 12 H). For Et3NH@ZnPzC: benzene,δ7.38 (singlet, 81 H); cyclohexane,δ1.40 (singlet, 12 H). S2

4 Crystal Data Table S1 Summary of the crystal data and structure refinement parameters Parameters NH Formula C 12H 6N 7O 10Zn 3 M r Space group Pa-3 a (Å) (17) b (Å) (17) c (Å) (17) (deg) 90 (deg) 90 (deg) 90 V (Å 3 ) (12) Z 8 D calcd (g cm -3 ) (mm -1 ) Reflections collected 7598 Unique reflections 2714 R int a R 1 [I>2 (I)] b wr 2 [I>2 (I)] a R 1 (all data) b wr 2 (all data) GOOF a R1= ( F0 - Fc )/ F0 ; b wr2=[ w(f0 2 - Fc 2 ) 2 / w(f0 2 ) 2 ] 1/2 Table S2. Selected bond lengths (Å) and bond angles ( ) Zn(1)-O(1)# (3) O(1)#1-Zn(1)-O(3) (14) Zn(1)-N(2) 1.983(3) N(2)-Zn(1)-O(3) 97.24(11) Zn(1)-N(1)# (3) N(1)#2-Zn(1)-O(3) 96.61(11) Zn(1)-O(3) (15) N(2)-Zn(1)-O(2)# (13) Zn(1)-O(2)# (3) N(1)#2-Zn(1)-O(2)# (14) Zn(1)-O(1)# (3) O(3)-Zn(1)-O(2)# (13) Zn(1)-N(2) 1.983(3) Zn(1)#2-O(3)-Zn(1)# (11) O(1)#1-Zn(1)-N(2) (15) N(1)-N(2)-Zn(1) 118.6(2) O(1)#1-Zn(1)-N(1)# (15) N(2)-N(1)-Zn(1)# (2) N(2)-Zn(1)-N(1)# (14) Symmetry code: #1 y,-z+1/2,x-1/2 #2 z,x,y #3 y,z,x S3

5 T (%) Additional Physical Measurements Figure S1 TG analysis of the exchanged samples Inset: Qualitative detection of the released gas. Upon heating at about 320 C under N2 flow, there is gas released from the sample, which can make a wet ph test paper change color to dark green, meaning the released gas is alkaline and most likely NH3 gas Wavenumber (cm -1 ) Figure S2 IR spectrum of NH4@ZnPzC. Inexistence of the strong band at 1658 cm 1 indicated deprotonation of all the H2PyC, the 1550 cm -1 and 1450 cm -1 peaks are asymmetrical stretching vibration and symmetrical stretching vibration of COO -, respectively. S4

6 Et 3 NH@ZnPzC Me 3 NH@ZnPzC Tb@ZnPzC Mg@ZnPzC Li@ZnPzC NH Simulated (degree) Figure S3 PXRD patterns of the exchanged samples A@ZnPzC after activation at 85 C under vacuum for 48 hours. Tb@ZnPzC Mg@ZnPzC Li@ZnPzC Et 3 NH@ZnPzC Me 3 NH@ZnPzC NH As-synthesized samples θ (degree) Figure S4 PXRD patterns of A@ZnPzC after immersing A@ZnPzC into boiling water for 24 hours. S5

7 Gas Adsorption Data and Analysis Calculation of isosteric heat of adsorption (Qst): The Clausius-Clapeyron equation was employed to calculate the enthalpies of CO2 adsorption: [ ln p ( 1 T )] n = Q st R (S-1) Where p is the pressure, n is the amount adsorbed, T is the temperature, R is the universal gas constant. The isosteric heat of adsorption Qst was subsequently obtained from the slope of plots of (ln P)n as a function of 1/T. Before using equation S-1, the Pressure-uptake relation of each isotherm was fitted using the empirical equations derived from the dual-site Langmuir-Freundlich equation: q = q m,1 b 1 p 1 n1 + q 1 m,2b 2 p n 2 1+b 1 p 1 n1 1+b 2 p 1 n2 (S-2) Here, P is the pressure of the bulk gas at equilibrium with the adsorbed phase (atm), q is the adsorbed amount per mass of adsorbent (mmol/g), qm,1 and qm,2 are the saturation capacities of sites 1 and 2 (mmol/g), b1 and b2 are the affinity coefficients of sites 1 and 2 (1/atm), and n1 and n2 represent the deviations from an ideal homogeneous surface. Prediction of the Gases Adsorption Selectivity by IAST: IAST (ideal adsorption solution theory) of Prausnitz and Myers was used to estimate binary mixture adsorption from the experimental pure-gas isotherms. Experimental absolute isotherm data were fit to the dual-site Langmuir-Freundlich isotherm for CO2 and N2 adsorption. The fitted parameters were then used to predict multi-component adsorption. The mole fraction of each species in the adsorbed phase can be calculated by solving the expression: py i x i n i (p) 0 p dp = S6 py j x j n j (p) 0 p dp (S-3)

8 Quantity adsorbed (mmol g -1 ) Quantity adsorbed (mmol g -1 ) where xi and yi are the adsorbed and bulk phase mole fractions of component i, respectively. In order to solve for xi, two quantities must be specified, specifically P and yi. The quantity xi was determined using numerical analysis and root exploration. The selectivity for component i relative to component j can be calculated via the following: s i = x i y j j x j y i (S-4) Figure S5 Dual-site Langmuir-Freundlich equation fitting (lines) of NH4@ZnPzC for the CO2 adsorption isotherms (points) measured at 298 (black), 303 (red), and 308 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S3 The obtained Dual-site Langmuir-Freundlich fitting parameters. T (K) qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S7

9 Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Figure S6 Dual-site Langmuir-Freundlich equation fitting (lines) of Me3NH@ZnPzC for the CO2 adsorption isotherms (points) measured at 298 (black), 303 (red), and 308 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S4 The obtained Dual-site Langmuir-Freundlich fitting parameters. T (K) qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S8

10 Quantity Adsorbed (mmol g -1 ) Figure S7 Dual-site Langmuir-Freundlich equation fitting (lines) of Et3NH@ZnPzC for the CO2 adsorption isotherms (points) measured at 298 (black), 303 (red), and 308 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S5 The obtained Dual-site Langmuir-Freundlich fitting parameters. T (K) qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S9

11 Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Figure S8 Dual-site Langmuir-Freundlich equation fitting (lines) of Li@ZnPzC for the CO2 adsorption isotherms (points) measured at 298 (black), 303 (red), and 308 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S6 The obtained Dual-site Langmuir-Freundlich fitting parameters. T (K) qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S10

12 Quantity Adsorbed (mmol g -1 ) Figure S9 Dual-site Langmuir-Freundlich equation fitting (lines) of Mg@ZnPzC for the CO2 adsorption isotherms (points) measured at 298 (black), 303 (red), and 308 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S7 The obtained Dual-site Langmuir-Freundlich fitting parameters. T (K) qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S11

13 Quantity Adsorbed (mmol g -1 ) Figure S10 Dual-site Langmuir-Freundlich equation fitting (lines) of Tb@ZnPzC for the CO2 adsorption isotherms (points) measured at 298 (black), 303 (red), and 308 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S8 The obtained Dual-site Langmuir-Freundlich fitting parameters. T (K) qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S12

14 Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Quantity Adsored (mmol g -1 ) E Figure S11 Dual-site Langmuir-Freundlich equation fitting (lines) of NH4@ZnPzC (top) and Me3NH@ZnPzC (down) for the CO2 (black) and N2 (red) adsorption isotherms (points) measured at 273 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S9 The obtained Dual-site Langmuir-Freundlich fitting parameters. NH4@ZnPzC Me3NH@ZnPzC CO2 N2 CO2 N2 qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S13

15 Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Figure S12 Dual-site Langmuir-Freundlich equation fitting (lines) of Et3NH@ZnPzC (top) and Li@ZnPzC (down) for the CO2 (black) and N2 (red) adsorption isotherms (points) measured at 273 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S10 The obtained Dual-site Langmuir-Freundlich fitting parameters. Et3NH@ZnPzC Li@ZnPzC CO2 N2 CO2 N2 qm,1 (mmol/g) qm,2 (mmol/g) b1 (atm -1 ) b2(atm -1 ) t t R S14

16 Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Quantity Adsorbed (mmol g -1 ) Figure S13 Dual-site Langmuir-Freundlich equation fitting (lines) of Mg@ZnPzC (top) and Tb@ZnPzC (down) for the CO2 (black) and N2 (red) adsorption isotherms (points) measured at 273 K (blue) (left: linear axis, right: logarithm axis). It can be seen that the fitting is good at all the pressure ranges measured. Table S11 The obtained Dual-site Langmuir-Freundlich fitting parameters. Mg@ZnPzC Tb@ZnPzC CO2 N2 CO2 N2 qm,1 (mmol/g) qm,2 (mmol/g) E-4 b1 (atm -1 ) b2(atm -1 ) E7 t t R S15

17 Table S12 Adsorption data for N2 gas at 77 K in A@ZnPzC NH4@ZnPzC Me3NH@ZnPzC Et3NH@ZnPzC Li@ZnPzC Mg@ZnPzC Tb@ZnPzC Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) 3.04E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E Et3NH@ZnPzC continued S16

18 Table S13 Desorption data for N2 gas at 77 K in A@ZnPzC NH4@ZnPzC Me3NH@ZnPzC Et3NH@ZnPzC Li@ZnPzC Mg@ZnPzC Tb@ZnPzC Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) S17

19 Table S14 Adsorption and desorption data for N2 gas at 273K in Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) S18

20 Table S15 Adsorption data for CO2 gas at 273K in Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) S19

21 Table S16 Desorption data for CO2 gas at 273K in Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) S20

22 Table S17 Adsorption and desorption data for CO2 gas at 298K, 303K and 308K in and respectively 298K 303K 308K 298K 303K 308K Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) S21

23 S22

24 Table S18 Adsorption and desorption data for CO2 gas at 298K, 303K and 308K in and respectively 298K 303K 308K 298K 303K 308K Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) Q (mmol/g) S23