Supporting Information

Transcription

1 Supporting Information Three-Dimensional Metal-Catecholate Frameworks and their Ultrahigh Proton Conductivity Nhung T. T. Nguyen,, Hiroyasu Furukawa, Felipe Gándara, Christopher A. Trickett, Hyung Mo Jeong, Kyle E. Cordova,, and Omar M. Yaghi,,* Department of Chemistry, University of California Berkeley; Materials Sciences Division, Lawrence Berkeley National Laboratory; Kavli Energy NanoSciences Institute at Berkeley, and Global Science Institute at Berkeley, Berkeley, California 94720, United States Center for Molecular and NanoArchitecture (MANAR), Vietnam National University Ho Chi Minh City, Ho Chi Minh City , Vietnam Department of New Architectures in Materials Chemistry, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Madrid 28049, Spain King Abdulaziz City of Science and Technology, Riyadh 11442, Saudi Arabia *To whom correspondence should be addressed: , S1

2 Table of Contents Section S1 General Methods S3 Section S2 Synthesis and Characterization of M-CATs S4-S5 Section S3 Scanning Electron Microscopy S6-S7 Section S4 X-ray Diffraction Analysis S8-S14 Section S5 Powder X-ray Diffraction S15-S16 Section S6 Fourier Transform Infrared Spectroscopy S17-S18 Section S7 Proton Nuclear Magnetic Resonance Analysis S19-S21 Section S8 Mössbauer Spectroscopy S22 Section S9 Thermal Gravimetric Analyses (TGA) S23 Section S10 N2 Adsorption Measurements S24 Section S11 Water Adsorption Measurements S25 Section S12 Air and Chemical Stability S26-S29 Section S13 Alternating Current Impedance Spectroscopy S30-S40 S2

3 Section S1: General Methods Chemicals used in this work. Iron(II) sulfate helptahydrate (FeSO4 7H2O), titanium(iv) isopropoxide (TTIP), vanadium(iii) chloride, tetrabutylammonium bromide (NBu4Br), tetrabutylammonium nitrate (NBu4NO3), amylamine were purchased from Sigma Aldrich Chemical Co. 2,3,6,7,10,11-Hexahydroxytriphenylene [HHTP = H6THO; THO -6 = triphenylene- 2,3,6,7,10,11-hexakis(olate)] was obtained from TCI America. N,N-Dimethylformamide (DMF) was obtained from BHD Chemical Co. Methanol and acetonitrile were obtained from EMD Millipore Chemicals. All of these chemicals were used without further purification. Experimental and Analytical techniques. Single crystal diffraction data were collected at beam line of the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory (LBNL) using synchrotron radiation with wavelength λ = Å. Powder X-ray diffraction (PXRD) patterns were collected using a Bruker D8 Advance employing Ni filtered Cu Kα (λ = Å). Fourier transform infrared (FT-IR) spectra were recorded on a Bruker ALPHA Platinum ATR-FT- IR Spectrometer equipped with a single reflection diamond ATR module. Solution proton nuclear magnetic resonance ( 1 H NMR) spectra were acquired on a Bruker AVB-400 NMR spectrometer. Thermal gravimetric analysis (TGA) curves were recorded on a TA Q500 thermal analysis system under air flow. Elemental microanalyses (EA) were performed in the Microanalytical Laboratory of the College of Chemistry at UC Berkeley, using a Perkin Elmer 2400 Series II CHNS elemental analyzer. Low-pressure N2 adsorption isotherms were recorded on a Quantachrome Quadrasorb SI volumetric gas adsorption analyzer. A liquid nitrogen bath was used for the measurements at 77 K. S3

4 Section S2: Synthesis Procedure and Characterization Synthesis of Fe(THO) Fe(SO 4 )(Me 2 NH 2 ) 3 (DMF) 0.65 H 2 O (Fe-CAT-5): A mixture of FeSO4 7H2O (0.044 g, 0.16 mmol), H6THO (0.050 g, 0.15 mmol), and NBu4NO3 (0.050 g, 0.16 mmol) were dissolved in the solvent mixture of DMF/water/methanol (5/0.5/0.5 ml). To facilitate the deprotonation of H6THO, 20 μl of amylamine was added. The solution mixture was stirred under a nitrogen atmosphere for 1 h before being transferred into a Teflon-lined, stainless steel Parr autoclave (Model 4749 general purpose bomb, inner volume = 23 ml). The autoclave was tightly capped and placed in an isothermal oven pre-heated at 180 C (internal pressure was auto generated and not specifically monitored). After 48 h, the autoclave was removed from the isothermal oven and allowed to cool down to room temperature. The black truncated octahedral single crystals were collected by centrifugation at 4000 rpm for 5 min and washed with DMF (3 2 ml). To prepare guest free samples, as-synthesized Fe-CAT-5 was immersed in DMF (10 ml for 1 d) and anhydrous acetonitrile (10 ml for 3 d), during which the solvent was replenished 5 and 9 times, respectively. The acetonitrile solvent was removed at room temperature under vacuum for 24 h, yielding guest free material. Yield: 36% based on H6THO. EA of activated sample: Calcd. for Fe2C25.95H30.55O11.65N3.65S = Fe(THO) Fe(SO4)(Me2NH2)3(DMF)0.65H2O: C, 43.05; H, 4.25; N, 7.06; S, 4.43%. Found: C, 43.28; H, 4.81; N, 7.25; S, 5.00%. FT-IR (ATR-IR, cm -1 ): 3208 (w), 2781 (w), 2438 (w), 1660 (w), 1595 (w), 1470 (s), 1417 (s), 1244 (s), 1116 (w), 1068 (w), 994 (w), 881 (s), 854 (m), 807 (m), 697 (s), 642 (s), 580 (s), 488 (s), 436 (w), 417 (w), 405 (w). Synthesis of Ti(THO) (Me 2 NH 2 ) 2 (C 3 H 7 OH) 0.06 (DMF) 0.06 (CH 3 CN) 0.04 H 2 O (Ti-CAT-5): H6THO (0.050 g, 0.15 mmol) and NBu4Br (0.050 g, 0.16 mmol) were dissolved in DMF (5 ml), followed by the addition of TTIP (45 L). To facilitate the deprotonation of H6THO, 20 L of amylamine was added. The reaction mixture was stirred under nitrogen atmosphere for 1 h before being transferred into a Teflon-lined, stainless steel Parr autoclave (Model 4749 general purpose bomb, inner volume = 23 ml). The autoclave was tightly capped and placed in an isothermal oven pre-heated at 180 C (internal pressure was auto generated and not specifically monitored). After 48 h, the autoclave was removed from the isothermal oven and allowed to cool down to room temperature. The microcrystalline powder was collected by centrifugation at 4000 rpm for 5 min S4

5 and washed with DMF (3 2 ml). To prepare guest free samples, as-synthesized Ti-CAT-5 was immersed in DMF (10 ml for 1 d) and anhydrous acetonitrile (10 ml for 3 d), during which the solvent was replenished 5 and 9 times, respectively. The acetonitrile solvent was removed at room temperature under vacuum for 24 h, yielding guest free material. Yield: 55% based on H6THO. EA of activated sample: Calcd. for TiC22.44H19.02N2.10O7.12 = Ti(THO) (Me2NH2)2(C3H7OH)0.06(DMF)0.06(CH3CN)0.04H2O: C, 56.16; H, 3.99; N, 6.13%. Found: C, 56.02; H, 4.19; N, 6.05%. FT-IR (ATR-IR, cm -1 ): 3053 (w), 2774 (w), 1603 (w), 1444 (s), 1250 (s), 1157 (w), 1055 (w), 1019 (w), 988 (m), 849 (w), 816 (s), 716 (w), 633 (w), 508 (s). Synthesis of V(THO) (Me 2 NH 2 ) 2 (DMF) 0.3 (CH 3 CN)(H 2 O) 3 (V-CAT-5): Vanadium(III) chloride (0.035 g, 0.22 mmol), H6THO (0.050 g, 0.15 mmol), and NBu4Br (0.10 g, 0.31 mmol) were dissolved in DMF (5 ml). The reaction mixture was stirred under nitrogen atmosphere for 1 h before being transferred into a Teflon-lined, stainless steel Parr autoclave (Model 4749 general purpose bomb, inner volume = 23 ml). The autoclave was tightly capped and placed in an isothermal oven pre-heated at 180 C (internal pressure was auto generated and not specifically monitored). After 48 h, the autoclave was removed from the isothermal oven and allowed to cool down to room temperature. The microcrystalline compound was collected by centrifugation at 4000 rpm for 5 min and washed with DMF (3 2 ml). To prepare guest free samples, assynthesized V-CAT-5 was immersed in DMF (10 ml for 1 d) and anhydrous acetonitrile (10 ml for 3 d), during which the solvent was replenished 5 and 9 times, respectively. The acetonitrile solvent was removed at room temperature under vacuum for 24 h, yielding guest free material. Yield: 62% based on H6THO. EA of activated sample: Calcd. for VC24.90H27.10N3.30O9.30 = V(THO) (Me2NH2)2(DMF)0.3(CH3CN)(H2O)3. C, 52.25; H, 4.77; N, 8.08%. Found: C, 51.75; H, 4.90; N, 7.68%. FT-IR (ATR-IR, cm -1 ): 1543 (w), 1459 (w), 1421 (w), 1344 (m), 1314 (m), 1241 (m), 1153 (m), 1046 (w), 985 (w), 816 (m), 695 (m), 603 (m), 496 (m). S5

6 Section S3: Scanning Electron Microscopy Scanning electron microscopy (SEM) analysis was performed on as-synthesized samples of Fe- CAT-5, Ti-CAT-5, and V-CAT-5 by dispersing each material onto a silicon wafer attached to a flat aluminum sample holder. The samples were then analyzed using a Zeiss Gemini Ultra-55 Analytical scanning electron microscope with accelerating voltage of 5 kv. Figure S1. SEM image of Fe-CAT-5. Scale bar: 20 μm. S6

7 Figure S2. SEM image of Ti-CAT-5. Scale bar: 300 nm. Figure S3. SEM image of V-CAT-5. Scale bar: 3 μm. S7

8 Section S4: X-ray Diffraction Analysis Single crystal X-ray diffraction data collection and structural solution for Fe-CAT-5 A colorless block shaped crystal ( mm) was mounted for collection of single crystal data at the beam line of the Advanced Light Source (ALS), using synchrotron using a silicon (111) reflection radiation with wavelength λ = Å. Samples were mounted on MiTeGen kapton loops and placed in a 100(2) K nitrogen cold stream provided by an Oxford Cryostream 700 Plus low temperature apparatus on the goniometer head of a Bruker D8 diffractometer equipped with a PHOTON100 CMOS detector operating in shutterless mode. An approximate full-sphere of data was collected using a combination of phi and omega scans with scan speeds of 2 seconds per 4 degrees for the phi scans, and 5 and 10 seconds per degree for the omega scans at 2θ = 0 and -45, respectively. The frames were integrated with the Bruker SAINT software package using a narrow-frame algorithm. The integration of the data using a cubic unit cell yielded a total of reflections to a maximum θ angle of (0.99 Å resolution), of which 999 were independent (average redundancy , completeness = 99.9%, Rint = 18.30%, Rsig = 2.95%) and 811 (81.18%) were greater than 2σ(F 2 ). The final cell constants of a = (7) Å and V = (7) Å 3 are based upon the refinement of the XYZ-centroids of reflections above 20σ(I). The final anisotropic fullmatrix least-squares refinement on F 2 with 156 variables converged at R1 = 6.11%, for the observed data and wr2 = 17.51% for all data. The goodness-of-fit was The largest peak in the final difference electron density synthesis was e - Å -3 and the largest hole was e - Å -3 with an RMS deviation of e - Å -3. On the basis of the final model, the calculated density was g cm -3 and F(000), 2908 e -. S8

9 Table S1. Crystal data and structure refinement for Fe-CAT-5. Empirical formula Fe8C103.8H122.2O46.6N14.6S4 Formula mass Temperature (K) 100 Crystal system Cubic Space group Pa-3 (Å) a (Å) (7) V (Å 3 ) (7) Z 1 Density (g cm -1 ) Absorption coefficient (mm -1 ) F(000) Crystal size (mm) θ range ( ) 2.17 to Index ranges -17 h 17, -17 k 17, -17 l 17 Reflections collected Independent reflections 999 [Rint = ] Coverage of independent reflections 99.9% Data / restraints / parameters 999 / 1 / 156 S (GOF) R1, wr2 [I > 2σ(I)] , R1, wr2 (all data) , Largest diff. peak and hole and e Å -3 S9

10 X-ray diffraction analyses, unit cell determination, electron density calculations, structural modeling, and Rietveld refinement for Ti-CAT-5 and V-CAT-5 X-ray data collection. PXRD data were collected using a Bruker D8-advance θ-θ diffractometer in reflectance Bragg-Brentano geometry employing Ni filtered Cu Kα lines focused radiation ( Å, Å) at 1600 W (40 kv, 40 ma) power and equipped with a Lynxeye detector, with an electronic window of 6, fitted at 0.6 mm radiation entrance slit. Samples were mounted on zero background sample holders by dropping powders from a wide-blade spatula and then leveling the sample with a razor blade. The best counting statistics were achieved by collecting samples using a θ step scan from 3 90 with exposure time of 10 seconds per step for Ti- CAT-5 and 5 seconds per step for V-CAT-5. All measurements were performed under ambient temperature and pressure. Figure S4. PXRD patterns of Ti-CAT-5 (red), and V-CAT-5 (green). Calculated PXRD patterns of simulated single srs net (black) and doubly interpenetrating srs-2c net (blue) are also overlaid. S10

11 Initial unit cell parameters were obtained by indexing the experimental PXRD patterns with the program X-cell, included in the Reflex module of Materials Studio 7.0. A cubic unit cell was suggested for both Ti-CAT-5 and V-CAT-5, with a = Å and Å, respectively. A full pattern profile matching (Pawley) refinement was then performed to extract the intensities of the experimental PXRD patterns. A Pearson VII function was used to describe the profile, with a 20 coefficient polynomial background. The structures were solved with the charge-flipping method, by using the program Superflip. Solutions were obtained in the P213 (Ti-CAT-5) and P4332 (V-CAT-5) space groups. Crystal models were constructed based on the atomic coordinates obtained from the resulting electron density maps, where the position of the metal cations and the organic H6THO linkers were clearly identified, with a disposition corresponding to an srs topology, which is doubly interpenetrated in the case of the Ti-CAT-5 (Figures S2a and S3a). A Rietveld refinement was then carried out to refine the crystal structures. Based on the results of the elemental analysis and spectroscopic evidences, dimethylammonium (DMA) molecules were included in the structures occupying the framework cavities. Their positions were refined with rigid body constraints. In the case of Ti-CAT-5, the DMA cations are found in two crystallographically independent positions, with 2/3 of atomic occupancy. As for the V-CAT-5, DMA cations are found in one crystallographic position, with 1/3 of atomic occupancy. Additional residual electron density attributed to solvent molecules was found in V-CAT-5, and an oxygen atom was included to account for it. The best refinement was obtained by using a pseudo Voigt function to refine the profile in the case of the Ti-CAT-5, while for V-CAT-5 a Pearson VII function combined with a Berar-Baldinozzi function for asymmetry correction was used. In both cases, a global isotropic parameter was used to define the thermal motion of the structures. Finally, preferred orientation effects were corrected with a Rietveld-Toraya function. S11

12 Figure S5. (a) Electron density map of Ti-CAT-5 exhibits a doubly interpenetrating framework. (b) Crystal structure of Ti-CAT-5. Atom colors: C, black; O, red; Ti, blue polyhedra. Second framework is shown in orange. Hydrogen atoms are omitted for clarity. S12

13 Figure S6. (a) Electron density map of V-CAT-5 shows clearly positions of V atoms and H6THO linkers. The octahedral secondary building units are shown in (b). (c) Crystal structure of V-CAT- 5. Atom colors: C, black; O, red; V, blue polyhedra. Hydrogen atoms are omitted for clarity. S13

14 Table S2. Final refinement parameters of Ti-CAT-5 and V-CAT-5. Name Ti-CAT-5 V-CAT-5 Refined composition Ti8C176H160N16O48 V4C88H80N8O32 Mass formula (g mol -1 ) Crystal system Cubic Cubic Space group P213 P4332 a (Å) (5) (8) V (Å 3 ) (3) (7) Crystal density (g cm -3 ) Rp (%) Rwp (%) S14

15 Section S5: Powder X-ray Diffraction Patterns Figure S7. As-synthesized (blue) and activated (red) PXRD patterns of Fe-CAT-5. Calculated pattern is also overlaid (black). Figure S8. As-synthesized (blue) and activated (red) PXRD patterns of Ti-CAT-5. Calculated pattern is also overlaid (black). S15

16 Figure S9. As-synthesized (blue) and activated (red) PXRD patterns of V-CAT-5. Calculated pattern is also overlaid (black). S16

17 Section S6: Fourier Transform Infrared Spectroscopy (FT-IR) Figure S10. FT-IR spectra of H6THO linker (black) and activated Fe-CAT-5 (red). Figure S11. FT-IR spectra of H6THO linker (black) and activated Ti-CAT-5 (red). S17

18 Figure S12. FT-IR spectra of H6THO linker (black) and activated V-CAT-5 (red). S18

19 Section S7: Proton Nuclear Magnetic Resonance Analyses Fe-CAT-5 (ca. 8 mg) was dispersed into 700 µl of MeOD-d4 and 30 µl of DCl (20% in D2O), which was sonicated for 5 min to fully digest the sample. Ti-CAT-5 and V-CAT-5 were digested following similar procedures, where these samples (ca. 8 mg) were dissolved in 100 µl of DCl (20% in D2O) and 700 µl of DMSO-d6. DO OD 1 DO DO 1 OD OD H 2 2 H 3 C N CH 3 2 H 3 O + MeOH DMF Chemical Shift / ppm Figure S13. 1 H NMR spectrum of Fe-CAT-5 after digesting in MeOD-d4/DCl solution. The result of peak integration indicates the mole ratio of D6HTO:DMA = 1:3. The presence of DMF was confirmed by attempting to add DMF into the digested Fe-CAT-5 sample which resulted in increasing the intensity at two peaks assigned for DMF. The signals of OD from D6HTO and NH from DMA were not observed on the spectrum. S19

20 Figure S14. 1 H NMR spectrum of Ti-CAT-5 after digesting in DMSO-d6/DCl solution. The result of peak integration indicates the mole ratio of D6HTO:DMA = 1:2. S20

21 Figure S15. 1 H NMR spectrum of V-CAT-5 after digesting in DMSO-d6/DCl solution. The result of peak integration indicates the mole ratio of D6HTO:DMA = 1:2. S21

22 Section S8: Mössbauer Spectroscopy The Iron-57 Mössbauer spectrum of Fe-CAT-5 was obtained at 5 K with a constant acceleration spectrometer and a Cobalt-57 Rhodium source. Prior to the measurement the spectrometer was calibrated at 5 K with -iron foil. The sample was diluted with boron nitride and transferred to the sample holder, which contained 30 mg cm -2 of Fe-CAT-5 or around 4.5 mg cm -2 of iron. The result shows the presence of Fe(III) and Fe(II) sites with ratio of 58 : 42, respectively, which is slightly deviated from the ideal value of 50 : 50 based on single crystal data. The small deviation might be due to some Fe(II) sites being oxidized during the measurement. Figure S16. Mössbauer spectrum of Fe-CAT-5 with collected data in black diamonds and the fit represented by the red line. The red has two components which are assigned to Fe(III) site (blue, = mm s -1, EQ = mm s -1, area = 58%) and Fe(II) site (green, = mm s -1, EQ = mm s -1, area = 42%). S22

23 Section S9: Thermal Gravimetric Analyses (TGA) The thermal stability of three CATs was examined by thermal gravimetric analysis. The TGA curve of Fe-CAT-5 demonstrated no significant weight loss until 200 C, confirming the thermal stability of Fe-CAT-5. TGA traces of Ti-CAT-5 and V-CAT-5 showed small weight loss of ca. 4% from C which could be attributed to the evaporation of guest solvents (i.e. DMF and CH3CN) from the pores. Figure S17. TGA trace for activated Fe-CAT-5 (red), Ti-CAT-5 (blue), and V-CAT-5 (green) at a heating rate of 5 C min -1 in air. S23

24 Section S10: N2 Adsorption Measurements The porosity of activated all three 3D-CAT materials were evaluated by N2 adsorption analysis. Type-I isotherms were observed for Ti-CAT-5 and V-CAT-5, whereas Fe-CAT-5 was almost nonporous, in agreement with the calculated value from its single crystal structure. Figure S18. N2 isotherms of Fe-CAT-5 (red), Ti-CAT-5 (blue), and V-CAT-5 (green) measured at 77 K. Filled and open symbols represent adsorption and desorption branches, respectively. The connecting curves are guides for the eye. Table S3. Brunauer Emmett Teller (BET), Langmuir surface area, and pore volume of three CAT compounds. Compounds Surface area (m 2 g -1 ) BET Langmuir Pore volume (cm 3 g -1 ) Fe-CAT Ti-CAT V-CAT S24

25 Section S11: Water Adsorption Measurements Figure S19. Water isotherms of Fe-CAT-5 (red) and Ti-CAT-5 (blue) measured at 298 K. Filled and open symbols represent adsorption and desorption branches, respectively. The connecting curves are guides for the eye. S25

26 Section S12: Air and Chemical Stability Air Stability. The air stability of three CATs was examined by simply exposing the samples to air for 24 h. The PXRD patterns of Fe-CAT-5 and Ti-CAT-5 demonstrate that crystallinity of these CATs remains, while the crystallinity of V-CAT-5 decreased after 3 h of air exposure. Figure S20. PXRD patterns of as-synthesized Fe-CAT-5 before (blue) and after air exposure for 24 h (red). S26

27 Figure S21. PXRD patterns of as-synthesized Ti-CAT-5 before (blue) and after air exposure for 24 h (red). Figure S22. PXRD patterns of as-synthesized V-CAT-5 before (blue) and after air exposure for 3 h (red). S27

28 Chemical Stability. The chemical stability of activated CAT materials was examined by immersing the sample in water, methanol, acetonitrile, and dichloromethane at room temperature for 3 d. The PXRD patterns collected for these samples demonstrate that all three CATs retain their crystallinity in all solvents tested. Figure S23. PXRD patterns of Fe-CAT-5 after immersing in different solvents for 3 d. S28

29 Figure S24. PXRD patterns of Ti-CAT-5 after immersing in different solvents for 3 d. Figure S25. PXRD patterns of V-CAT-5 after immersing in different solvents for 3 d. S29

30 Section S13: Alternating Current Impedance Analysis Proton conductivity measurements were implemented on pelletized samples of Fe-CAT-5 and Ti- CAT-5 pressed in a disk at 54 kpsi. The alternating current impedance analysis was performed on the pellets using two-probe method on Biologic VMP3 multichannel potentiostatic-galvanostatic system with impedance model. An Espec SH-242 humidity control chamber was used to control the humidity and temperature for the measurements. The pellets were stabilized under humid conditions for 20 h before subjecting to ac impedance analysis and the data were collected from 1 MHz 10 Hz. The resistance was determined by equivalent circuit fitting the semicircle of the Nyquist plot (Scheme 1). The activation energy was calculated from the slope of the Arrhenius plot of data collected from variable temperature under the constant relative humidity using the Arrhenius equation = ( 0/T)exp(-Ea/kT), where is conductivity, 0 is a pre-exponential factor, T is temperature, k is the Boltzmann constant, and Ea is the activation energy. Scheme 1. An equivalent circuit used for fitting. Schematic representations: R1/R2/R3, resistor; C2, capacitor; Q3, imperfect capacitor. S30

31 Figure S26. PXRD comparison of pelleted Fe-CAT-5 before (blue) and after (red) exposure to 98% RH in order to demonstrate the stability of Fe-CAT-5 under the most extreme proton conductivity conditions used in this work. S31

32 Figure S27. PXRD comparison of pelleted Ti-CAT-5 before (blue) and after (red) exposure to 98% RH in order to demonstrate the stability of Ti-CAT-5 under the most extreme proton conductivity conditions used in this work. S32

33 Figure S28. Nyquist plots (black squares) and fitted plots (red curve) of Fe-CAT-5 at 50% (a), 60% (b), 70% (c), 80% (d), 90% (e), and 98% RH (f). S33

34 Figure S29. The dependence of proton conductivity on relative humidity for Fe-CAT-5 is shown for two consecutive cycles demonstrating no obvious degradation in performance. S34

35 Figure S30. Nyquist plots of Fe-CAT-5 based on varying pellet dimensions, but consistent thickness at 98% RH. As is shown, the resistance increased with decreasing pellet dimensions; however, it is noted that the proton conductivities extracted from this data remained the same, regardless of the pellet dimensions. S35

36 Figure S31. Dependence of proton conductivity in Fe-CAT-5 as a function of time is shown. Fe- CAT-5 was exposed to 95% RH at the appropriate temperature for 20 h prior to performing ac impedance measurements. S36

37 Figure S32. Nyquist plots (black squares) and fitted plots (red curve) of Ti-CAT-5 at 50% (a), 60% (b), 70% (c), 80% (d), 90% (e), and 98% RH (f). S37

38 Figure S33. Arrhenius plots of Fe-CAT-5 and Ti-CAT-5. S38

39 Figure S34. PXRD pattern of Fe-CAT-5 immediately after ac impedance analysis. Figure S35. PXRD pattern of Ti-CAT-5 immediately after ac impedance analysis. S39

40 Figure S36. Speculative proton pathway conduction for Fe-CAT-5 based on single crystal X-ray data showing the actual positions of DMA and sulfate ions within the structure (a). Noncontributing atoms to the proton conduction were removed to reveal a hydrogen-bonded network created by DMA and sulfate (b). The proposed pathway for the proton transport within Fe-CAT-5 upon addition of water (c). The blue dash lines represent the hydrogen-bond distance between DMA and sulfate. The green lines represent the distance between two DMA ions. Atom colors: Fe, blue and pink polyhedral; DMA, green; S, yellow; O, red; all H atoms are omitted for clarity. S40