Supplementary Information

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1 Supplementary Information Partitioning MOF-5 into confined and hydrophobic compartments for carbon capture under humid conditions Nan Ding, Haiwei Li, Xiao Feng,* Qianyou Wang, Shan Wang, Li Ma, Junwen Zhou, Bo Wang* Contents Section A. Materials and methods Section B. Experimental section Section C. Supplementary spectra (Figure S1-S34) Section D. Supporting references S1

2 Section A. Materials and method All reagents and starting materials were obtained commercially and were used as received without any further purification. 1,2-diiodobenzene and naphthalene-2,6-dicarboxylic acid (H 2 NDC) were purchased from J&K Chemical. Zn(NO 3 ) 2 6H 2 O, ZrCl 4, Cu(NO 3 ) 2 3H 2 O, benzene-1,4-dicarboxylic acid (H 2 BDC), 2-amino-4,4 -dicarboxylicacid (NH 2 -BDC) and1,3,5-benzenetricarboxylic (H 3 BTC) were purchased from Energy Chemical. DMF, petroleum ether and chloroform were purchased from Beijing Chemical Works. 1 H NMR spectra were recorded on a Bruker ARX-400 spectrometer. The solid-state 13 C NMR spectra measurements were performed on Agilent DD2 NMR 400MHz NMR Spectrometer with one NMR probe. Powder X-ray diffraction (PXRD) patterns of the samples were analyzed with a Cu-Kα X-ray radiation source (λ = nm) incident radiation by a Bruker Foucus D8 diffractometer instrument operating at 40 kv voltage and 50 ma current. PXRD patterns were recorded from 1.5 to 50 (2θ) at 298 K. N 2 sorption isotherms were measured at 77 K on a Quantachrome Instrument ASiQMVH002-5 after pretreatment (samples were degassed at 120 C for 6 h). The pore size distributions were estimated by the DFT method from a N 2 sorption experiment at 77 K. CO 2 sorption isotherms were measured at the same instrument after pretreatment. Field-emission scanning electron microscopy (FE-SEM) images were acquired from a JEOL model S-4800 scanning electron microscope. S2

3 Elemental analyses (C, H) were conducted on EuroEA Elemental Analyser. Zn content was determined by a PLASMA-SPEC (I) ICP atomic emission spectrometer. The fourier transform infrared attenuated total reflection (FTIR-ATR) spectra were recorded in the range cm -1 on Bruker ALPHA spectrometer. Water contact angle measurements were carried out on OCA 20 optical contact angle meter at ambient conditions. S3

4 Section B. Synthetic procedures Synthesis of 1,2-diethynylbenzene (a) 1,2-Bis((trimethylsilyl)ethynyl)benzene: I + Si I Pd(Ph 3 P) 4, CuI toluene, Et 3 N Si Si 1,2-Bis((trimethylsilyl)ethynyl)benzene was synthesized according to the reported procedure with slight modification. 1 Under a nitrogen atmosphere, ethynyltrimethylsilane (5.40 g, 55.0 mmol) was added to a solution of 1,2-diiodobenzene (6.50 g, 19.7 mmol) in deoxygenated triethylamine (TEA, 50 ml) and toluene (50 ml) with Pd(PPh 3 ) 4 (0.68 g, 0.6 mmol) and CuI (0.11 g, 0.6 mmol) in a 250 ml three-necked bottle at 25 C. Then stirred for 20 additional hours at this temperature. Then the reaction mixture was filtered, and the filtrate was concentrated on a rotary evaporator. The crude residue was purified by column chromatography on silica gel with petroleum ether as eluent to give pure 1,2-bis((trimethylsilyl)ethynyl)benzene as a yellow oil, 4.79 g (90% yield). 1 H NMR (400 MHz, CDCl 3 ): δ 0.27 (s,18h), 7.24 (q,2h), 7.47 (q,2h). (b) Synthesis of 1,2-diethynylbenzene: Si Si K 2 CO 3 CH 2 Cl 2, MeOH S4

5 1,2-diethynylbenzene was synthesized according to the reported procedure with slight modification. 2 A solution of 1,2-bis((trimethylsilyl)ethynyl)benzene (6.30 g, 23.3 mmol) in dichloromethane/methanol (v/v = 1:1, 600 ml) was treated with (8.06 g, mmol) of K 2 CO 3 at room temperature for 12 hours. After the removal of organic solvent, water was added and the aqueous solution was extracted with dichloromethane three times. The dichloromethane solution was dried over sodium sulfate. After solvent evaporation, the residue was purified by column chromatography on silica gel with petroleum ether as eluent to give 1,2-diethynylbenzene as red oil, 2.47 g (84% yield). 1 H NMR (400 MHz, CDCl 3 ): δ 3.35 (s, 2H), 7.32 (q, 2H), 7.53 (q, 2H). Preparation of MOF-5 and UMCM-8 MOF-5 was prepared according to the reported procedure with slight modification. 3 Zinc nitrate hexahydrate (4.50 g, 15.0 mmol) and 1,4-benzenedicarboxylic acid (0.83 g, 5.0 mmol) were dissolved in 490 ml of DMF and 10 ml H 2 O in a 1000 ml jar with a teflon lined lid. The reaction mixture was heated in an oven at 100 C for 7 h to yield cube-shaped crystals. The solvent was decanted, and the remaining solid was washed three times with 500 ml of anhydrous DMF, each time letting the solid soak in DMF for 8 h. The DMF was then decanted, and the solid washed three times with 500 ml of CHCl 3, again each time letting the solid soak in CHCl 3 for 8 h. After the final CHCl 3 wash, the solvent was decanted and the included CHCl 3 was removed under vacuum to give colorless cube-shaped crystals, 0.65 g. S5

6 UMCM-8 was prepared according to the reported procedures. 4 The resultant product was obtained as pale yellow crystals (yield, 35%). Procedure of polymerization of 1,2-diethynylbenzene (DEB) in MOFs (a) Controlling the monomer loadings in MOFs A typical procedure is as follows. The host compound MOF-5 (0.20 g) was first activated by evacuation (<0.1kPa) at 120 C for 6 h. Then MOF-5 was immersed in the mixture of DEB (300 µl) and petroleum ether (300 µl) for 2 h aiming at fully introducing the monomer into the nanochannels. Then the excess monomer was removed by filtration and further washed with petroleum ether. The loadings were tuned by adjusting the amounts of petroleum ether used for washing. PN@MOF-5 and PN were obtained by washing with 100 and 250 ml petroleum ether, respectively. PN was prepared by using similar method. (b) Procedure of polymerization Putting the above samples into the ampoules, then the samples were flash frozen in a liquid nitrogen bath, evacuated and flame sealed. After warming to room temperature, the ampoules were placed in an oven at 170 C for 12 h. (c) PN isolated from PN@MOF inclusions The inclusion was stirred in aqueous solution of HCl (10 M) for 4 h to decompose the porous framework of MOF-5. The solid obtained was washed with DMF and CHCl 3 and the residue was dried under reduced pressure at room temperature and analyzed by 13 C NMR spectroscopy. S6

7 Section C: Supplementary spectra Figure S1. 1 H NMR spectrum of 1,2-Bis((trimethylsilyl)ethynyl)benzene S7

8 Figure S2. 1 H NMR spectrum of 1,2-diethynylbenzene S8

9 Figure S3. Digital photographs of (a) MOF-5, (b) PN and (c) Figure S4. Solid ultraviolet spectra of MOF-5 and S9

10 Figure S5. PXRD patterns of MOF-5, PN and Figure S6. PXRD pattern of PN. S10

11 Table S1. Elemental analysis results. Samples C (%) H (%) Zn (%) PN loading (g/g) MOF PN % PN@MOF % Bulk PN Figure S7. 13 C solid state NMR spectra of PN@MOF-5, MOF-5, PN isolated from MOF-5 and PN. S11

12 Figure S8. FTIR-ATR spectra of MOF-5, DEB and PN. Figure S9. SEM images of (a) MOF-5, (b) PN and (c) S12

13 Figure S10. (a-c) Optical micrographs of (a) MOF-5, (b) PN and (c) (d-g) The crystals of PN and (d-e) before and (f-g) after dissection. S13

14 Figure S11. N 2 adsorption/desorption isotherms of MOF-5, PN and PN@MOF-5. S14

15 Figure S12. BET equation fitting curve for MOF-5 N 2 isotherm. BET surface area, 3200 m 2 g -1. S15

16 Figure S13. BET equation fitting curve for PN N 2 isotherm. BET surface area, 2600 m 2 g -1. S16

17 Figure S14. BET equation fitting curve for N 2 isotherm. BET surface area, 1200 m 2 g -1. S17

18 Figure S15. N 2 adsorption isotherms of PN and PN at 77K. S18

19 Figure S16. CO 2 sorption isotherms of PN and PN at 273 K. PN@MOF-5 with 34% weight loading exhibits a BET surface area of 400 m 2 /g and CO 2 capacity of 47 cm 3 /g; the sample with 40% weight loading exhibits almost no N 2 sorption ability but shows a CO 2 capacity of 30 cm 3 /g. Due to the nature of the PN polymer chains, our strategy is indeed a careful balance between partitioning the MOF channels and partially blocking. S19

20 Figure S17. Pore size distribution of based on CO K isotherm sorption profile using NLDFT model. Smaller ultramicropores are observed is because CO 2 molecules with 3.3 Å kinetic diameter at 273 K can more easily access ultramicropores than N 2 with larger kinetic diameter (3.64 Å) at 77 K. S20

21 Figure S18. Isosteric heats of CO 2 adsorption for PN@MOF-5 and MOF-5. S21

22 N 2 and CO 2 sorption analyses of pure PN Figure S19. N 2 adsorption isotherm of PN collected at 77 K. Figure S20. Pore size distribution of PN based on N 2-77 K isotherm sorption profile using QSDFT equilibrium model. S22

23 Figure S21. CO 2 sorption isotherm of PN at 273 K. These results indicate that the BET surface area of pure PN is only 30 m 2 /g and its pore size is mainly distributed ranging from 2.4 to 24 nm. The CO 2 capacity of PN is as low as 5 cm 3 /g at 273 K and 1 bar. It is noteworthy that PN polymer chains, like many other aromatic polymers, tend to stack, aggregate and bury most of their surfaces and edges. Without well-oriented and constrained pores of MOFs, pure PN can barely uptake gas molecules. Considering the scenario where all the PN polymers are adsorbed on the surface, the BET surface area is calculated to be ~2700 m 2 /g on the basis of the contributions of each component to the total surface area of PN@MOF-5, which is much higher than its real BET surface area of 1200 m 2 /g. The SEM and optical images, pore size distribution analyses (sharp distribution at 0.6 and 1.2 nm) and PXRD measurements (no broad diffraction peak is observed around 5 to 32 o as in the pure PN polymer) all unambiguously demonstrated that most of the PN polymers are indeed distributed inside MOF pores. The MOF scaffold and S23

24 polymer inside should be considered as an entirety that is responsible for CO 2 capture, and the contribution of the pure PN polymer in CO 2 adsorption is negligible comparing that of the MOF or the PN@MOF. S24

25 Ideal adsorbed solution theory (IAST) selectivity calculations Ideal Adsorbed Solution Theory (IAST) of Myers and Prausnitz along with the pure component isotherm fits was applied to determine the molar loadings in the gas mixture for specified partial pressures in the bulk gas phase. The pure component isotherms of CO 2 measured were fitted with the dual-site Langmuir (DSL) model: The pure component isotherms of N 2 measured were fitted with the single-site Langmuir (SSL) model: where, q is molar loading of adsorbate (mmol g 1 ), q sat is saturation loading (mmol g 1 ), b is parameter in the pure component Langmuir isotherm (bar 1 ), p is bulk gas phase pressure (bar). Pure-component isotherm fitting parameters were then used for calculating IAST binary-gas adsorption selectivities (S ads ). S ads is defined as: S25

26 Figure S22. N 2 adsorption isotherms of MOF-5 and PN@MOF-5 collected at 273 K. The increased IAST selectivity (212 vs. 9, PN@MOF-5 vs. MOF-5) was indeed associated with the dramatically improved CO 2 adsorption capacity (Fig. 1b) as well as the diminished N 2 adsorption (Fig. S22). S26

27 Table S2: Comparison of selectivity for CO 2 /N 2 mixture in different MOFs MOFs Temperature CO 2 /N 2 Reference selectivity PN@MOF K 212 a in this work PCN K 22 a Nat. Commun. 2013, 4, 1538 [Cu(tba) 2 ] n 273 K 51 a J. Am. Chem. Soc. 2014, 136, InOF K 551 a Chem. Commun. 2012, 48, SIFSIX-3-Zn 298 K 1818 c Nature, 2013, 495, NJU-Bai8 273 K b J. Am. Chem. Soc. 2013, 135, CAU K 34 b Energy Environ. Sci. 2011, 4, bio-mof K 81 b J. Am. Chem. Soc. 2010, 132, [Cu 3 (BTB 6- )] n 273 K 34.2 b Chem. Commun. 2012, 48, bio-mof K 123 c Chem. Sci. 2013, 4, Mg-MOF K 49 d Angew. Chem. Int. Ed. 2012, 51, HKUST K 13 d Chem. Mater. 2009, 21, ZIF K 50 b J. Am. Chem. Soc. 2009, 131, UiO K a Chem. Eur. J. 2015, 21, SNU-21S 298 K 2.73 d Chem. Commun. 2011, 47, MOF K 2.8 d J. Am. Chem. Soc. 2010, 132, MIL-101(Cr) 298 K 11 d Sci. Rep. 2013, 3, a: IAST-predicted adsorption selectivity from CO 2 /N 2 (15:85); b: Initial slope predicted adsorption selectivity; c: IAST-predicted adsorption selectivity from CO 2 :N 2 =10:90 d: Selectivity based on single-component gas adsorption isotherms. S27

28 Stability tests for PN Figure S23. PXRD patterns of PN@MOF-5 and MOF-5 after exposure to humidity for different times. S28

29 Figure S24. PXRD patterns of PN and MOF-5 after exposure to humidity for different times. S29

30 Figure S25. N 2 adsorption/desorption isotherms of PN before and after exposing to humidity for 8 h. The PN@MOF-5 with 3.2wt% PN loading can tolerate moisture (RH = 40%) within 8 h, which performs much better than MOF-5. We have optimized the PN loading in PN@MOF-5 samples and found that 15wt% PN loading exhibited balanced stability and CO 2 adsorption capacity. S30

31 Breakthrough Measurements The powder of was pelleted under 7 MPa of pressure and then packed into a 4 cm length 0.5 cm diameter stainless steel column to act as adsorbent bed. The CO 2 breakthrough experiments were performed on a laboratory-made, fixed-bed system at 298 K in dynamic conditions. To avoid the miscalculation of the breakthrough time and adsorption capacities, we installed a blank column in parallel to the adsorbent bed as a control as shown in the set-up drawing of the dynamic sorption (Fig. S26). Under dry condition test, the whole instrument was first saturated with a mixture of CO 2 /N 2 at 84:16 sccm by going through the blank bed including the gas line connected with a trace gas analyzer (an ESI-quadrapole mass spectrometer with a Faraday cup by Hiden Instrument), and then the gas flow through the absorbent bed would occur once we switched the flow to the adsorbent bed the sorbent bed. CO 2 breakthrough data was monitored by the Hiden HPR-20 QIC R&D quadrupole mass spectrometry and the breakthrough time could be calculated from the time point we changing the gas route to the breakthrough point (5%). The adsorption capacities could be estimated by the integration of the CO 2 content changing area and divided by the adsorbent weight as well as multiplied by the flow rate of the injected mixed gas. After one CO 2 breakthrough experiment was done, a purging process was sequentially conducted with ultrahigh-purity N 2 gas to sweep off all the CO 2 adsorbed in the sample and after that, the second trial was carried out. The same procedure was presented in the wet condition except that the testing gas mixture of CO 2 /N 2 at 84:16 sccm was at a relative humidity of 65% developed by a humidity generator. All S31

32 samples were purged with ultrahigh-purity N 2 gas for at least 30 min before testing. Figure S26. Installation drawing of the dynamic sorption. S32

33 Figure S27. Dynamic sorption curves of MOF-5 under dry conditions (blue) and in the presence of water (red). Figure S28. Dynamic sorption curves of under dry conditions (blue) and in the presence of water (red). S33

34 Figure S29. PXRD patterns of pelleted after dynamic sorption test, pelleted MOF-5 and pelleted MOF-5 after dynamic sorption test. S34

35 Preparation of MOF-199 and NH 2 -UiO-66 for breakthrough tests MOF-199 and NH 2 -UiO-66 were prepared according to the reported procedures. 5 Phase purity of these two MOFs was verified by PXRD measurements. The BET surface area of MOF-199 and NH 2 -UiO-66 are 1800 and 900 m 2 g -1. Figure S30. PXRD patterns of the simulated MOF-199 and synthesized MOF-199. S35

36 Figure S31. PXRD patterns of the simulated NH 2 -UiO-66 and synthesized NH 2 -UiO-66. Table S3 Breakthrough time of several MOFs MOFs MOF-5 PN@MOF-5 MOF-199 NH 2 -UiO-66 Breakthrough Dry Time(s/g) condition Wet condition N/A 656 N/A N/A N/A: not available. These two representative MOFs (NH 2 -UiO-66 and MOF-199) with polar functionalities or open metal sites exhibited long breakthrough time under dry conditions but drastically lost their CO 2 capacity under humid conditions. Unlike PN@MOF-5, which can still uptake and retain CO 2 under humid condition. The breakthrough time of NH 2 -UiO-66 and MOF-199 is too short to measure since the measured lowest concentration of CO 2 during the tests is higher than the breakthrough point, 5% of feed-in CO 2 concentration. S36

37 Stability tests and CO 2 sorption capacity of PN and UMCM-8 Figure S32. PXRD patterns of PN and UMCM-8 after exposure to humidity for 10 days. S37

38 Figure S33. N 2 adsorption/desorption isotherms of PN and UMCM-8 after exposure to humidity for 10 days. S38

39 Figure S34. CO 2 sorption isotherms of UMCM-8 and PN at 273 K. These results showed that PN exhibit remarkably improved stability towards moisture and increased adsorption capacity (56 vs. 39 at 273 K and 1bar). S39

40 Section D. Supporting references [1] Li, J. R.; Yakovenko, A. A.; Lu, W. G.; Timmons, D. J.; Zhuang, W. J.; Yuan, D. Q.; Zhou, H. C. J. Am. Chem. Soc. 2010, 132, [2] de Oteyza, D. G.; Gorman, P.; Chen, Y. C.; Wickenburg, S.; Riss, A.; Mowbray, D. J.; Etkin, G.; Pedramrazi, Z.; Tsai, H. Z.; Rubio, A.; Crommie, M. F.; Fischer, F. R. Science 2013, 340, [3] Steven, S. K.; Dailly, A.; Yaghi, O. M.; Long, J. R. J. Am. Chem. Soc. 2007, 129, [4] Koh, K.; Van Oosterhout, J. D.; Roy, S.; Wong-Foy, A. G.; Matzger, A. J. Chem. Sci. 2012, 3, 2429 [5] (a) Katz, M. J.; Brown, Z. J.; Colon, Y. J.; Siu, P. W.; Scheidt, K. A.; Snurr, R. Q.; Hupp, J. T.; Farha, O. K. Chem Commun. 2013, 49, (b) Xiang, S. C.; Zhou, W.; Gallegos, J. M.; Liu, Y.; Chen, B. L. J. Am. Chem. Soc. 2009, 131, S40