Additive-Induced Supramolecular Isomerism and Enhancement of

Subscriber access provided by University of South Dakota

Surfaces, Interfaces, and Applications

Additive-induced Supramolecular Isomerism and Enhancement of Robustness in Co(II) based MOFs for Efficiently Trapping Acetylene from Acetylene-Containing Mixtures Yingxiang Ye, Shimin Chen, Liangji Chen, Jitao Huang, Zhenlin Ma, Ziyin Li, Zizhu Yao, Jindan Zhang, Zhangjing Zhang, and Shengchang Xiang ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.8b11999 • Publication Date (Web): 20 Aug 2018 Downloaded from http://pubs.acs.org on August 29, 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 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 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.

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 15 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

ACS Applied Materials & Interfaces

Additive-induced Supramolecular Isomerism and Enhancement of Robustness in Co(II) based MOFs for Efficiently Trapping Acetylene from Acetylene-Containing Mixtures Yingxiang Ye,† Shimin Chen,† Liangji Chen,† Jitao Huang,†,§ Zhenlin Ma,† Ziyin Li,† Zizhu Yao,† Jindan Zhang,† Zhangjing Zhang,*†‡ and Shengchang Xiang*†‡ †

Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian

Normal University, 32 Shangsan Road, Fuzhou 350007, PR China ‡

State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese

Academy of Sciences, Fuzhou, 350002, PR China §

College of Chemistry and Materials Science, Ningde Normal University, Ningde, 352100, PR China

ABSTRACT: Although supramolecular isomerism in metal-organic frameworks (MOFs) would offer a favorable platform for in-depth exploring their structure-property relationship, the design and synthesis of the isomers are still rather a challenging aspect of crystal engineering. Here, a pair of supramolecular isomers of Co(II)-based MOFs (FJU-88 and FJU-89) can be directionally fabricated by rational tuning the additives. In spite of the fact that the isomers have the similar Co3 secondary building units (SBUs) and organic linkers, they adopt distinct networks with asc and snw topologies, respectively, which derive from the conformational flexibility of the organic ligands. It is noteworthy that the porous structure of FJU-88 would be collapsed after removal of the solvent from the pores. But FJU-89a shows permanent porosity accompanied with unusual hierarchical micro- and mesopores and superior gas selective adsorption performance. In addition, FJU-89a can efficiently trap C2H2 from C2H2/CO2 and C2H2/CH4 mixture gases through a fixed bed dynamic breakthrough experiments. KEYWORDS: metal-organic frameworks, supramolecular isomerism, hierarchically micro- and mesoporous, acetylene/carbon dioxide separation, acetylene/methane separation INTRODUCTION Acetylene (C2H2) is one of the significant fuel gas and essential raw materials in the petrochemical and electronic industry.1,2 Nowadays, there are two mainly acetylene preparation processes, one is derived from the thermal cracking of natural gas (>80% CH4)3 during which the separation of C2H2 from CH4 meets grade A requirement acetylene for organic synthesis, while the departure from the distillates produced during steam cracking in petroleum refining will produce a large number of byproducts (including CO2).4,5 However, the similarities between C2H2 and CO2 in 1 ACS Paragon Plus Environment

ACS Applied Materials & Interfaces 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

the perspective of their shapes, molecular dimensions (3.3×3.3×5.7 Å3 and 3.2×3.3×5.4 Å3 for C2H2 and CO2, respectively),6 and physical properties (boiling points of 189.3 for C2H2 and 194.7 K for CO2) make it a great challenge for C2H2 separation. Porous materials based adsorptive separation is considered to be a promising future separation technology with more environment-friendly and energy-efficient by compared with cryogenic distillation or organic solvent extraction.7,8 Among all kinds of solid porous materials,9-11 metal-organic framework materials are considered to be the most promising candidates for such an application. Metal-organic frameworks (MOFs),12,13 represent an intriguing type of crystalline porous materials (CPMs) that can be readily self-assembled through the coordination of inorganic metal ions/clusters with organic bridging linkers. In recent years, owing to the structural visualization and tunability,14 high surface areas15 and functional pore cages/channels,16 the bright potential of MOFs as emerging multifunctional materials is highlighted in many research areas, such as gas storage and separation, 17 - 22 liquid phase adsorption/separation, 23 chemical sensing, 24 ion conductors, 25 - 29 catalysis, 30 and biomedicine. 31 The term of supramolecular isomerism (or framework isomers) in MOFs was first reviewed by Moulton and Zaworotko in 2001,32 which can be divided into four main categories: structural, conformational, catenane or interpenetration and optical isomers.33-36 The study of supramolecular isomerism is an urgent demand due to which could provide a convenient platform for the effective construction of its structure-property relationship. Conformational isomers of MOFs contain the same building blocks (metal nodes and organic linkers) and identical stoichiometry, but they differ either by the conformation of flexible organic ligands or by the orientation of inorganic metal nodes. Although some external factors (e.g., temperature, solvent, pH value, and concentration)37-40 can be responsible for the construction of conformational isomerism, the difficulty in predicting and controlling the crystallization processes make the design and synthesis of the conformational isomers a challenging. To date, it was not observed that the conformation of the ligands as well as the overall topology in a pair of MOF conformational isomers was affected by the additives. In the present work, we have successfully obtained a pair of conformational isomers (FJU-88 and FJU-89), by using organic ligand 4-(p-carboxyphenyl)-1,2,4-triazole (HCPT), CoCl2·6H2O, and rational tuning the additive agent TPBTC (N,N',N''-tris(p-pyridyl)trimesic amide) (Scheme 1). FJU-88 crystallizes similarly to MIL-88 series (acs topology),41 but would be collapsed after removal of the solvent from the pores. In contrast, FJU-89 adopts the intriguing snw topological structure, shows permanent porosity with extraordinary hierarchical pores and superior gas selective adsorption property. Furthermore, FJU-89a can efficiently capture C2H2 from C2H2/CO2 and 2 ACS Paragon Plus Environment

Page 2 of 15

Page 3 of 15 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


C2H2/CH4 mixtures through a column breakthrough experiments. Scheme 1. Schematic representation of the syntheses of a pair of conformational isomers (FJU-88 and FJU-89).

EXPERIMENTAL SECTION Synthesis of [Co3(µ3-OH)(CPT)3(H2O)3]Cl2(DMA)5.5(H2O)5 (FJU-88). A mixture of HCPT (0.5 mmol, 0.094 g) and CoCl2·6H2O (0.5 mmol, 0.120 g) were dissolved in the mixed solution of DMA-H2O-HBF4 (21 mL, 10/3/1, v/v/v, DMA = N,N’-Dimethylacetamide), and then heated in 120 oC oven for 1 day. After cooling to room temperature, the light orange rod-shaped single crystals were obtained (yield: 65%, based on HCPT). Elemental analysis calculated (found) for [Co3(µ3-OH)(CPT)3(H2O)3]Cl2(DMA)5.5(H2O)5 (C49H84.5Co3N14.5Cl2O20.5): C, 40.52 (41.84); H, 5.86 (5.71); N, 13.98 (13.65). FT-IR (KBr, cm-1): 3417 (s), 3133 (s), 2924 (m), 1608 (s), 1541 (s), 1402 (s), 1246 (s), 1180 (w), 1093 (s), 864 (m), 785 (s), 696 (m), 624 (m), 517 (s) cm-1. Synthesis of [Co3(µ3-OH)(CPT)3(H2O)3]Cl2(DMA)6(H2O)6 (FJU-89). A mixture of HCPT (0.5 mmol, 0.094 g), CoCl2·6H2O (0.5 mmol, 0.12 g,) and TPBTC (0.23 mmol, 0.100 g,) were dissolved in the mixed solution of DMA-H2O-HBF4 (21 mL, 10/3/1, v/v/v) and then heated in 120 oC oven for 1 day. After cooling to room temperature, the orange bulk-shaped single crystals were obtained (yield: 55%, based on HCPT). Elemental analysis calculated (found) for [Co3(µ3-OH)(CPT)3(H2O)3]Cl2(DMA)6(H2O)6 (C51H91Co3N15Cl2O22): C, 40.46 (41.48); H, 6.06 (5.81); N, 13.88 (14.56). FT-IR (KBr, cm-1): 3417 (s), 3097 (s), 2939 (w), 1683 (w), 1606 (s), 1512 (s), 1398 (s), 1333 (m), 1297 (m), 1240 (m), 1089 (m), 1016 (m), 839 (m), 784 (s), 711 (w), 592 (m), 534 (m) cm-1. RESULTS AND DISCUSSION Synthesis and Characterization. In a typical synthesis, light orange rod-shaped crystals of FJU-88 were successfully synthesized by heating an equimolar mixture of HCPT and CoCl2·6H2O 3 ACS Paragon Plus Environment


at 120 oC for 1 day in the mixed DMA-H2O-HBF4 solution. Similarly, the additional supramolecular isomers FJU-89 with orange bulk-shaped crystals can be synthesized by adding TPBTC during this reaction. Obviously, the additives act as the template molecules and play an important role in controlling the supramolecular isomerism in this case, and the mechanistic details are still under investigation. Combining the results of thermogravimetric analysis (TGA) and elemental analysis, a pair of conformational isomers were formulated as [Co3(µ3-OH)(CPT)3(H2O)2]Cl2(DMA)5.5(H2O)5 for FJU-88 and [Co3(µ3-OH)(CPT)3(H2O)2]Cl2(DMA)6(H2O)6 for FJU-89. The phase purity of the as-synthesized sample (FJU-88 and FJU-89) was confirmed by the powder X-ray diffraction (PXRD) technology (Figures S6 and S7).

Figure 1. The trinuclear Co(II) unit and organic ligand HCPT in FJU-88 (a) and FJU-89 (f), and viewed as a 6-connected node and 2-connected linker, respectively. The coordination mode, and the twist angle between the plane of triazole ring and benzene ring of the CPT in FJU-88 (b) and FJU-89 (g). The trigonal bipyramidal cage Co15(CPT)6 and the twisted octahedral cage Co18(CPT)8 were observed in FJU-88 (c) and FJU-89 (h). (d) The 3D framework of FJU-88 showing hexagonal 1D channel view along the c axis, (i) the 3D framework of FJU-89 showing two types of 4 ACS Paragon Plus Environment

Page 4 of 15

Page 5 of 15 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


1D channels view along the a axis. Schematic view of the acs and snw topological structure in FJU-88 (e) and FJU-89 (j). Color code: Co, orange or light purple; O, red; N, blue; C, dark gray. Guest molecules and hydrogen atoms have been omitted for clarity. Structural Descriptions. Single-crystal X-ray diffraction analyses show that FJU-88 and FJU-89 have the analogous secondary building units (SBUs) and metal-ligand connection modes, but crystallizes in the hexagonal P63/mmc and tetragonal I41/amd space group, respectively, thus they belong to a pair of supramolecular isomers. The Co(II) ion is coordinated by four distinct CPT ligands, a µ3-OH- anion, and one terminal H2O molecule, with the octahedral geometry. Three Co(II) ions around a µ3-OH- group are connected by three triazole and three carboxyl groups from six independent CPT ligands to form a typical tri-prismatic SBUs (Figures 1a and 1f). Notably, there is a trigonal bipyramidal and twisted octahedral cage in FJU-88 and FJU-89 with its center at the Wyckoff position 4a and 2d, and the dimensions of these two cages are estimated to be around 8 and 12 Å, respectively (Figures 1c and 1h). Then, the trinuclear Co(II) SBUs are connected by the organic linkers (CPT) to form a three-dimension cationic open framework. FJU-88 shows a hexagonal 1D channel along the c axis (Figure 1d) with an aperture size of approximately 14 Å, whereas FJU-89 displays two types of (hexagonal and quadrilateral) 1D channels along the a axis, and with the pore size of circa 12 and 8 Å, respectively (Figure 1i). If the trinuclear Co(II) SBUs is viewed as six connected nodes and CPT as 2-connected linker, FJU-88 and FJU-89 adopt the acs and snw topological network,41,42 respectively, but with the equal point (Schläfli) symbol of {49·66} (Figures 1e and 1j). It was worth mentioning that the rare snw topology network was firstly fabricated by one-step strategy.42 After removing the free solvents, the total accessible volume of FJU-88 and FJU-89 is estimated to be 72.7% and 76.5%, respectively, as determined by PLATON.43 The average twist angle between the plane of triazole ring and benzene ring of CPT in FJU-88 and FJU-89 are 1.234o and 30.624o, 4.641o (Figures 1b and 1g), corresponding to relative conformational energies of 82.71 and 78.86, 82.41 kcal/mol,44 respectively. As the free ligand gives the most favorable value of 33.9o,44 which indicates the framework of FJU-88 is higher tension than FJU-89, while FJU-89 is more stable isomer than FJU-88.45

5 ACS Paragon Plus Environment


Figure 2. (a) 77 K N2 adsorption-desorption isotherms of FJU-89a. (b) The pore-size distribution (PSD) of FJU-89a from the 273 K CO2 and 77 K N2 isotherms based on the no-local density functional theory (NLDFT) model. (c) 273 K and (d) 296 K C2H2 (violet hexagon), CO2 (red circle), and CH4 (green diamond) adsorption isotherms of FJU-89a. Pore Textural Properties. For permanent porosity establishment, the freshly as-synthesized sample was soaked in anhydrous CH3OH to exchange the guest solvents, and then pumped under high vacuum at 333 K overnight to get guest-free phases FJU-88a and FJU-89a, respectively. As shown in Figure S10, the 77 K N2 adsorption of FJU-88a is much less and with no pore volume, which may be caused by the removal of solvent from pores and the collapse of porous structures, as the further PXRD patterns confirm (Figure S6). In contrast, the activated FJU-89a showed two types of combined isotherms, types I--a steep rise in the low-pressure range, and types IV--obvious adsorption-desorption hysteresis in the relative pressure range of 0.5 to 0.9 (Figure 2a). Such combined adsorption behavior has also been observed in other hierarchically porous MOFs.46 The Brunauer-Emmett-Teller (BET) and Langmuir surface area calculated from the N2 adsorption isotherms is 774 m2/g and 1202m2/g, respectively (Figure S11). The total pore volume obtained from the maximum N2 uptake is 0.68 cm3/g (including 0.32 cm3/g of micropore volume), slightly lower than the theoretical value of 1.16 cm3/g. The difference between theoretical and experimental results is mainly due to the shrinkage of the activated host framework, which was further confirmed by the PXRD patterns (Figure S7). The pore size distribution (PSD) of FJU-89a was calculated by using the NLDFT model, showing the coexistence of micropores and mesopores as the major pores 6 ACS Paragon Plus Environment

Page 6 of 15

Page 7 of 15 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


located in the range of 0.5-1.1 nm and 8-12 nm, respectively (Figure 2b). Gas Adsorption. Establishment of permanent porosity and optimized pore space within the framework of FJU-89a encourage us to study its adsorption and separation performances. At 273 K and 1 bar, the uptake capacity of C2H2, CO2, and CH4 are 123.3 cm3/g, 94.2 cm3/g-1, and 22.5 cm3/g, respectively (Figure 2c). Similarly, the uptake value of C2H2 is 101.4 cm3/g, which is higher than the values of CO2 (61.1 cm3/g) and CH4 (14.0 cm3/g), at 296 K and 1 bar (Figure 2d). Although the uptake capacity of C2H2 in FJU-89a at 296 K is lower than some famous MOFs with high density of open-metal sites (OMS), for example FJI-H8 (224 cm3/g),47 and HKUST-1 (201 cm3/g),48 the adsorbed C2H2 is comparable with FJU-22a (114.8 cm3/g),49 and TIFSIX-2-Cu-i (91.8 cm3/g)50 and much higher than ZJU-196a (83.5 cm3/g),51 UTSA-300a (68.9 cm3/g),52 and NKMOF-1-Ni (61.0 cm3/g).53 The zero surface coverage isosteric heat of adsorption (Qst) of C2H2, CO2, and CH4 for FJU-89a, derived from the 273 K and 296 K adsorption isotherms and fitted using the virial equation, are 31.0 kJ/mol, 27.8 kJ/mol, and 18.1 kJ/mol, respectively (Figure S12). Obviously, the interaction between C2H2 and host skeleton is stronger than that of CO2 and CH4. The notable differences among CH4, CO2, and C2H2 absorption behaviors indicate that FJU-89a might be a promising candidate for C2H2/CH4 and C2H2/CO2 separation. The well-defined ideal adsorbed solution theory (IAST)54 is also used to assess the separation selectivity of binary C2H2/CH4 (50%:50%) and C2H2/CO2 (50%:50%) mixtures at different pressures. At 296 K, the C2H2/CH4 selectivity range is from 42.6 to 65.9, and slightly lower than that of Cu-TDPAT (82)55 and FJU-12a (79.7)56 but significantly higher than that of UTSA-72a (26.5),57 and ZJU-199 (27.3 to 33.5),58 and the C2H2/CO2 selectivity range is from 4.3 to 6.6, and comparable to some famous MOFs, such as TIFSIX-2-Cu-i (10-6)50 and HKUST-1 (10-5).59 Similarly, at 273 K, the C2H2/CH4 and C2H2/CO2 selectivity range is from 54.5 to 84.2 and 4.0 to 6.6, respectively, which are quite high as well. These endue the FJU-89a unfold C2H2/CO2 and C2H2/CH4 separation proficiency (Figure S18).



Figure 3. Dynamic breakthrough curves for (a) C2H2/CO2/He and (b) C2H2/CH4/He gas mixture (5:5:90, v/v/v) in a fixed-bed packed with FJU-89a. The value of (c) adsorption capacity and (d) separation factor of FJU-89a in multiple breakthrough experiments. To further investigate the C2H2/CO2 and C2H2/CH4 separation performance of FJU-89 in actual process, we conducted lab-scale fixed-bed breakthrough tests at ambient conditions, in which the mixed-gas of C2H2/CO2/He (5:5:90, v/v/v) and C2H2/CH4/He (5:5:90, v/v/v) was flowed over a packed column of activated FJU-89a sample with a total flow of 7 mL/min and 12 mL/min, respectively. As shown in Figure 3a, CO2 was detected after the mixed-gas had been flowed into the fixed-bed for about 17.2 min, whereas C2H2 was not detected until the breakthrough time up to 57.2 min. Similarly, for C2H2/CH4/He gas mixtures, the breakthrough time of CH4 and C2H2 was 3 and 36 min, (Figure 3b) respectively. Thus, the mixed-gas of C2H2/CO2 and C2H2/CH4 through a column packed with FJU-89a adsorbent can be efficiently separated. It is noted that a roll-up behavior was observed for CO2, which may be due to a partial substitution of the adsorbed CO2 on the adsorption sites by the stronger adsorptive C2H2 in the gas mixtures.60 The dynamic C2H2 adsorption capacity in C2H2/CO2/He and C2H2/CH4/He mixtures based on the breakthrough time were found to be 0.94 and 1.04 mmol/g, respectively, which is close to the IAST-predicted result of 1.0 and 1.04 mmol/g (Figures S16 and S17). From the breakthrough curve, the separation factors, α = (q1y2)/(y1q2), were calculated to be 3.0 and 13.1 for the equimolar mixed-gas of C2H2/CO2 and C2H2/CH4. The separation factor of C2H2/CO2 in FJU-89a is lower than that of TIFSIX-2-Cu-i (50),50 UTSA-74a (20.1), 61 and DICRO-4-Ni-i (13), 62 but higher than the value of 2.0 for 8 ACS Paragon Plus Environment

Page 8 of 15

Page 9 of 15 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


HOF-3,59 and 1.9 for FJU-22a.49 Moreover, the separation factor (13.1) of C2H2/CH4 in FJU-89a is inferior to ZJNU-59 (26.2),63 but remarkably higher than the value of 5.2 for s-PMO-2.64 In the actual industrial applications, the ideal adsorbent should have good stability and recycling performance. We thus performed multiple C2H2/CO2/He and C2H2/CH4/He mixed-gas dynamic breakthrough experiments to evaluate the preservation of the separation property of FJU-89a. As shown in Figures 3c and 3d, the recycling experiments showed that the value of capture capacity and separation factor keeps steady during three dynamic breakthrough tests, further indicating that FJU-89a is a promising candidate for acetylene-containing mixture purification. CONCLUSIONS In conclusion, we have successfully prepared a pair of MOF conformational isomers by using bifunctional ligand HCPT with transition metal Co(II) and rational tuning the additive agents (TPBTC) under solvothermal reactions. It's worth noting that their host skeletons are constructed from the similar Co3 SBUs as well as the same organic linkers, but the resulting topology networks are remarkably different (acs and snw for FJU-88 and FJU-89, respectively), which originate from the conformational flexibility of the organic ligands. The pair of isomers exhibit notably distinct skeleton robustness upon guest exchange due to their different topology networks. FJU-89a shows permanent porosity accompanied with funny hierarchical micropores and mesopores and superior gas selective adsorption performance. In addition, dynamic breakthrough tests indicate that FJU-89a can efficiently trap C2H2 from C2H2/CO2 and C2H2/CH4 gas mixtures. Our investigation will give a new perspective on the elaborate structure-functionality relationship of MOFs and the rational design of novel hierarchically porous metal-organic frameworks. ASSOCIATED CONTENT Supporting Information Full experimental and instrumental details, additional structural figures, gas adsorption isotherms, PXRD patterns, FT-IR spectra, and TGA curves. This material is available free of charge via the Internet at http://pubs.acs.org. AUTHOR INFORMATION Corresponding Authors *[email protected] *[email protected] 9 ACS Paragon Plus Environment


ORCID Yingxiang Ye: 0000-0003-3962-8463 Zhangjing Zhang: 0000-0003-1264-7648 Shengchang Xiang: 0000-0001-6016-2587 Notes The authors declare no competing financial interests. ACKNOWLEDGMENTS This work was financially supported by the National Natural Science Foundation of China (21673039, 21573042, and 21273033), Fujian Science and Technology Department (2018J07001, 2016J01046, and 2014J06003). S. X. gratefully acknowledges the support of the Recruitment Program of Global Young Experts.


Page 10 of 15

Page 11 of 15 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


REFERENCES 1 2 3 4 5 6

7 8

9 10 11

12 13 14 15

16

17 18 19

20

Stang, P. J.; Diederich, F. Modern Acetylene Chemistry (VCH, New York, 1995). Zhang, Z.; Xiang, S.; Chen, B. Microporous Metal-Organic Frameworks for Acetylene Storage and Separation. CrystEngComm 2011, 13, 5983-5992. Henglein, F. A. Chemical Technology, Pergamon Press, Oxford, New York, 1st English edn, 1968. Passler, P.; Hefner, W.; Buckl, K.; Meinass, H.; Meiswinkel, A.; Wernicke, H.-J.; Ebersberg, G.; Muller, R.; Bassler, J.; Behringer, H. Acetylene. Ullmann’s Encyclopedia of Industrial Chemistry 2000, 1, 276-326. Guo, C. J.; Shen, D.; Bulow, M. 18-O-03-Kinetic Separation of Binary Mixtures of Carbon Dioxide and C2 Hydrocarbons on Modified LTA-Type Zeolites. Stud. Surf. Sci. Catal. 2001, 135, 2952-2960. Reid, C. R.; Thomas, K. M. Adsorption Kinetics and Size Exclusion Properties of Probe Molecules for the Selective Porosity in a Carbon Molecular Sieve Used for Air Separation. J. Phys. Chem. B 2001, 105, 10619-10629. Sholl, D. S.; Lively, R. P. Seven Chemical Separations to Change the World. Nature 2016, 532, 435-437. Cui, X.; Chen, K.; Xing, H.; Yang, Q.; Krishna, R.; Bao, Z.; Wu, H.; Zhou, W.; Dong, X.; Han, Y.; Li, B.; Ren, Q.; Zaworotko, M. J.; Chen, B. Pore Chemistry and Size Control in Hybrid Porous Materials for Acetylene Capture from Ethylene. Science 2016, 353, 141-144. Breck, D. W.; Eversole, W. G.; Milton, R. M.; Reed, T. B.; Thomas, T. L. Crystalline Zeolites. I. The Properties of a New Synthetic Zeolite, Type A. J. Am. Chem. Soc. 1956, 78, 5963-5972. Reid, C. R.; Thomas, K. M. Adsorption of Gases on a Carbon Molecular Sieve Used for Air Separation: Linear Adsorptives as Probes for Kinetic Selectivity. Langmuir 1999, 15, 3206-3218. Newalkar, B. L.; Choudary, N. V.; Turaga, U. T.; Vijayalakshmi, R. P.; Kumar, P.; Komarneni, S.; Bhat, T. S. G. Adsorption of Light Hydrocarbons on HMS Type Mesoporous Silica. Microporous Mesoporous Mater. 2003, 65, 267-276. Schoedel, A.; Li, M.; Li, D.; O’Keeffe, M.; Yaghi, O. M. Structures of Metal-Organic Frameworks with Rod Secondary Building Units. Chem. Rev. 2016, 116, 12466-12535. Furukawa, S.; Reboul, J.; Diring, S.; Sumida, K.; Kitagawa, S. Structuring of Metal-Organic Frameworks at the Mesoscopic/Macroscopic Scale. Chem. Soc. Rev. 2014, 43, 5700-5734. He, Y.; Li, B.; O’Keeffe, M.; Chen, B. Multifunctional Metal-Organic Frameworks Constructed from Meta-Benzenedicarboxylate Units. Chem. Soc. Rev. 2014, 43, 5618-5656. Férey, G.; Mellot-Draznieks, C.; Serre, C.; Millange, F.; Dutour, J.; Surblé, S.; Margiolaki, I. A Chromium Terephthalate-Based Solid with Unusually Large Pore Volumes and Surface Area. Science 2005, 309, 2040-2042. Hu, T. L.; Wang, H. L.; Li, B.; Krishna, R.; Wu, H.; Zhou, W.; Zhao, Y. F.; Han, Y.; Wang, X.; Zhu, W. D.; Yao, Z. Z.; Xiang, S. C.; Chen, B. Microporous Metal-Organic Framework with Dual Functionalities for Highly Efficient Removal of Acetylene from Ethylene/Acetylene Mixtures. Nat. Commun. 2015, 6, 7328. Zhang, Z.; Yao, Z. Z.; Xiang, S.; Chen, B. Perspective of Microporous Metal-Organic Frameworks for CO2 Capture and Separation. Energy Environ. Sci. 2014, 7, 2868-2899. Lin, R.-B.; Xiang, S.; Xing, H.; Zhou, W.; Chen, B. Exploration of Microporous Metal-Organic Frameworks for Gas Separation and Purification. Coord. Chem. Rev. 2018, doi.org/10.1016/j.ccr.2017.09.027. Li, L.; Lin, R.-B.; Krishna, R.; Wang, X.; Li, B.; Wu, H.; Li, J.; Zhou, W.; Chen, B. Flexible-Robust Metal-Organic Framework for Efficient Removal of Propyne from Propylene. J. Am. Chem. Soc. 2017, 139, 7733-7736. Wen, H.-M.; Li, L.; Lin, R.-B.; Li, B.; Hu, B.; Zhou, W.; Hu, J.; Chen, B. Fine-Tuning of Nano-Traps in a Stable Metal-Organic Framework for Highly Efficient Removal of Propyne from Propylene. J. Mater. Chem. A 2018, 6, 6931-6937.



21 Wang, H.; Dong, X.; Lin, J.; Teat, S. J.; Jensen, S.; Cure, J.; Alexandrov, E. V.; Xia, Q.; Tan, K.; Wang, Q.; Olson, D. H.; Proserpio, D. M.; Chabal, Y. J.; Thonhauser, T.; Sun, J.; Han, Y.; Li, J. Topologically Guided Tuning of Zr-MOF Pore Structures for Highly Selective Separation of C6 Alkane Isomers. Nat. Commun. 2018, 9, 1745. 22 Wang, L.; Ye, Y.; Li, Z.; Lin, Q.; Ouyang, J.; Liu, L.; Zhang, Z.; Xiang, S. Highly Selective Adsorption of C2/C1 Mixtures and Solvent Dependent Thermochromic Properties in Metal-Organic Frameworks Containing Infinite Copper-Halogen Chains. Cryst. Growth Des. 2017, 17, 2081-2089. 23 Zhang, Q.; Cui, Y.; Qian, G. Goal-Directed Design of Metal-Organic Frameworks for Liquid-Phase Adsorption and Separation. Coord. Chem. Rev. 2018, doi.org/10.1016/j.ccr.2017.10.028. 24 Cui, Y.; Li, B.; He, H.; Zhou, W.; Chen, B.; Qian, G. Metal-Organic Frameworks as Platforms for Functional Materials. Acc. Chem. Res. 2016, 49, 483-493. 25 Ye, Y.; Wu, X.; Yao, Z.; Wu, L.; Cai, Z.; Wang, L.; Ma, X.; Chen, Q.; Zhang, Z.; Xiang, S. Metal-Organic Frameworks with a Large Breathing Effect to Host Hydroxyl Compounds for High Anhydrous Proton conductivity over a Wide Temperature Range from Subzero to 125 oC. J. Mater. Chem. A 2016, 4, 4062-4070. 26 Ye, Y.; Zhang, L.; Peng, Q.; Wang, G.; Shen, Y.; Li, Z.; Wang, L.; Ma, X.; Chen, Q.; Zhang, Z.; Xiang, S. High Anhydrous Proton Conductivity of Imidazole-Loaded Mesoporous Polyimides over a Wide Range from Subzero to Moderate Temperature. J. Am. Chem. Soc. 2015, 137, 913-918. 27 Ye, Y.; Guo, W.; Wang, L.; Li, Z.; Song, Z.; Chen, J.; Zhang, Z.; Xiang, S.; Chen, B. Straightforward Loading of Imidazole Molecules into Metal-Organic Framework for High Proton Conduction. J. Am. Chem. Soc. 2017, 139, 15604-15607. 28 Han, Y. H.; Ye, Y.; Tian, C.; Zhang, Z.; Du, S. W.; Xiang, S. C. High Proton Conductivity in an Unprecedented Anionic Metalloring Organic Framework (MROF) Containing Novel Metalloring Clusters With the Largest Diameter. J. Mater. Chem. A 2016, 4, 18742-18746. 29 Li, Z.; Zhang, Z.; Ye, Y.; Cai, K.; Du, F.; Zeng, H.; Tao, J.; Lin, Q.; Zheng, Y.; Xiang, S. Rationally Tuning Host-Guest Interactions to Free Hydroxide Ions within Intertrimerically Cuprophilic Metal-Organic Frameworks for High OH− Conductivity. J. Mater. Chem. A 2017, 5, 7816-7824. 30 Otake, K.-i.; Cui, Y.; Buru, C. T.; Li, Z.; Hupp, J. T.; Farha, O. K. Single-Atom-Based Vanadium Oxide Catalysts Supported on Metal-Organic Frameworks: Selective Alcohol Oxidation and Structure-Activity Relationship. J. Am. Chem. Soc. 2018, 140, 8652-8656. 31 Lan, G.; Ni, K.; Lin, W. Nanoscale Metal-Organic Frameworks for Phototherapy of Cancer. Coord. Chem. Rev. 2017, doi.org/10.1016/j.ccr.2017.09.007. 32 Moulton, B.; Zaworotko, M. J. From Molecules to Crystal Engineering: Supramolecular Isomerism and Polymorphism in Network Solids. Chem. Rev. 2001, 101, 1629-1658. 33 Panda, T.; Pachfule, P.; Banerjee, R. Template Induced Structural Isomerism and Enhancement of Porosity in Manganese (II) Based Metal-Organic Frameworks (Mn-MOFs). Chem. Commun. 2011, 47, 7674-7676. 34 Panda, T.; Kundu, T.; Banerjee, R. Structural Isomerism Leading to Variable Proton Conductivity in Indium (III) Isophthalic Acid Based Frameworks. Chem. Commun. 2013, 49, 6197-6199. 35 Ma, S.; Sun, D.; Ambrogio, M.; Fillinger, J. A.; Parkin, S.; Zhou, H. C. Framework-Catenation Isomerism in Metal-Organic Frameworks and Its Impact on Hydrogen Uptake. J. Am. Chem. Soc. 2007, 129, 1858-1859. 36 Tong, X.-L.; Hu, T.-L.; Zhao, J.-P.; Wang, Y.-K.; Zhang, H.; Bu, X.-H. Chiral Magnetic Metal-Organic Frameworks of MnII with Achiral Tetrazolate-Based Ligands by Spontaneous Resolution. Chem. Commun. 2010, 46, 8543-8545. 37 Sun, D. F.; Ke, Y. X.; Mattox, T. M.; Ooro, B. A.; Zhou, H. C. Temperature-Dependent Supramolecular Stereoisomerism in Porous Copper Coordination Networks Based on a Designed Carboxylate Ligand. Chem.


Page 12 of 15

Page 13 of 15 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


Commun. 2005, 5447-5449. 38 Chen, D. M.; Ma, X. Z.; Shi, W.; Cheng, P. Solvent-Induced Topological Diversity of Two Zn (II) Metal-Organic Frameworks and High Sensitivity in Recyclable Detection of Nitrobenzene. Cryst. Growth Des. 2015, 15, 3999-4004. 39 Perman, J. A.; Chen, M.; Mikhail, A. A.; Niu, Z.; Ma, S. Acid-Base Directed Supramolecular Isomers of Isophthalate Based MOFs for CO2 Adsorption and Transformation. CrystEngComm 2017, 19, 4171-4174. 40 Jiang, H.-L.; Tatsu, Y.; Lu, Z.-H.; Xu, Q. Non-, Micro-, and Mesoporous Metal-Organic Framework Isomers: Reversible Transformation, Fluorescence Sensing, and Large Molecule Separation. J. Am. Chem. Soc. 2011, 132, 5586-5587. 41 Serre, C.; Mellot-Draznieks, C.; Surble, S.; Audebrand, N.; Filinchuk, Y.; Ferey, G. Role of Solvent-Host Interactions That Lead to Very Large Swelling of Hybrid Frameworks. Science 2007, 315, 1828-1831. 42 Schoedel, A.; Wojtas, L.; Kelley, S. P.; Rogers, R. D.; Eddaoudi, M.; Zaworotko, M. J. The asc Trinodal Platform: Two-Step Assembly of Triangular, Tetrahedral, and Trigonal-Prismatic Molecular Building Blocks. Angew. Chem., Int. Ed. 2011, 50, 11421-11424. 43 Spek, A. L. Spek, A. L. Single-Crystal Structure Validation with the Program PLATON. J. Appl. Crystallogr. 2003, 36, 7-13. 44 Chen, D.-M.; Tian, J.-Y.; Fang, S.-M.; Liu, C.-S. Two Isomeric Zn(II)-Based Metal-Organic Frameworks Constructed from a Bifunctional Triazolate-Carboxylate Tecton Exhibiting Distinct Gas Sorption Behaviors. CrystEngComm 2016, 18, 2579-2584. 45 He, C.-T.; Liao, P.-Q.; Zhou, D.-D.; Wang, B.-Y.; Zhang, W.-X.; Zhang, J.-P.; Chen, X.-M. Visualizing the Distinctly Different Crystal-to-Crystal Structural Dynamism and Sorption Behavior of Interpenetration-Direction Isomeric Coordination Networks. Chem. Sci. 2014, 5, 4755-4762. 46 Park, J.; Wang, Z. U.; Sun, L. B.; Chen, Y. P.; Zhou, H. C. Introduction of Functionalized Mesopores to Metal-Organic Frameworks via Metal-Ligand-Fragment Coassembly. J. Am. Chem. Soc. 2012, 134, 20110-20116. 47 Pang, J.; Jiang, F.; Wu, M.; Liu, C.; Su, K.; Lu, W.; Yuan, D.; Hong, M. A Porous Metal-Organic Framework with Ultrahigh Acetylene Uptake Capacity under Ambient Conditions. Nat. Commun. 2015, 6, 7575. 48 Xiang, S.; Zhou, W.; Gallegos, J. M.; Liu, Y.; Chen, B. Exceptionally High Acetylene Uptake in a Microporous Metal-Organic Framework with Open Metal Sites. J. Am. Chem. Soc. 2009, 131, 12415-12419. 49 Yao, Z.; Zhang, Z.; Liu, L.; Li, Z.; Zhou, W.; Zhao, Y.; Han, Y.; Chen, B.; Krishna, R.; Xiang, S. Extraordinary Separation of Acetylene-Containing Mixtures with Microporous Metal-Organic Frameworks with Open O Donor Sites and Tunable Robustness through Control of the Helical Chain Secondary Building Units. Chem.-Eur. J. 2016, 22, 5676-5683. 50 Chen, K.-J.; Scott, H. S.; Madden, D. G.; Pham, T.; Kumar, A.; Lusi, M.; Forrest, K.; Space, B.; Perry, J. J., IV; Zaworotko, M. J. Benchmark C2H2/CO2 and CO2/C2H2 Separation by Two Closely Related Hybrid Ultramicroporous Materials. Chem 2016, 1, 753-765. 51 Zhang, L.; Jiang, K.; Li, L.; Xia, Y.-P.; Hu, T.-L.; Yang, Y.; Cui, Y.; Li, B.; Chen, B.; Qian, G. Efficient Separation of C2H2 from C2H2/CO2 Mixtures in an Acid-Base Resistant Metal-Organic Framework. Chem. Commun. 2018, 54, 4846-4849. 52 Lin, R.-B.; Li, L.; Wu, H.; Arman, H.; Li, B.; Lin, R.-G.; Zhou, W.; Chen, B. Optimized Separation of Acetylene from Carbon Dioxide and Ethylene in a Microporous Material. J. Am. Chem. Soc. 2017, 139, 8022-8028. 53 Peng, Y.-L.; Pham, T.; Li, P.; Wang, T.; Chen, Y.; Chen, K.-J.; Forrest, K. A.; Space, B.; Cheng, P.; Zaworotko, M. J.; Zhang, Z. Robust Ultramicroporous Metal-Organic Frameworks with Benchmark Affinity for Acetylene. Angew. Chem., Int. Ed. 2018, DOI: 10.1002/anie.201806732.



54 Myers, A. L.; Prausnitz, J. M. Thermodynamics of Mixed-Gas Adsorption. AIChE J. 1965, 11, 121-127. 55 Liu, K.; Ma, D.-X.; Li, B.-Y.; Li, Y.; Yao, K.-X.; Zhang, Z.-J.; Han, Y.; Shi, Z. High Storage Capacity and Separation Selectivity for C2 Hydrocarbons over Methane in the Metal-Organic Framework Cu-TDPAT. J. Mater. Chem. A 2014, 2, 15823-15828. 56 Chen, Y.; Li, Z.; Liu, Q.; Shen, Y.; Wu, X.; Xu, D.; Ma, X.; Wang, L.; Chen, Q.-H.; Zhang, Z.; Xiang, S. Microporous Metal-Organic Framework with Lantern-like Dodecanuclear Metal Coordination Cages as Nodes for Selective Adsorption of C2/C1 Mixtures and Sensing of Nitrobenzene. Cryst. Growth Des. 2015, 15, 3847-3852. 57 Alawisi, H.; Li, B.; He, Y. B.; Arman, H.; Asiri, A.; Wang, H.; Chen, B. A Microporous Metal-Organic Framework Constructed from a New Tetracarboxylic Acid for Selective Gas Separation. Cryst. Growth Des. 2014, 14, 2522-2526. 58 Zhang, L.; Zou, C.; Zhao, M.; Jiang, K.; Lin, R.; He, Y.; Wu, C.- D.; Cui, Y.; Chen, B.; Qian, G. Doubly Interpenetrated Metal-Organic Framework for Highly Selective C2H2/CH4 and C2H2/CO2 Separation at Room Temperature. Cryst. Growth Des. 2016, 16, 7194-7197. 59 Li, P.; He, Y. B.; Zhao, Y. F.; Weng, L. H.; Wang, H. L.; Krishna, R.; Wu, H.; Zhou, W.; O’Keeffe, M.; Han, Y.; Chen, B. L. A Rod-Packing Microporous Hydrogen-Bonded Organic Framework for Highly Selective Separation of C2H2/CO2 at Room Temperature. Angew. Chem., Int. Ed. 2015, 54, 574-577. 60 Yoon, J. W.; Jang, I. T.; Lee, K.-Y.; Hwang, Y. K.; Chang, J.-S. Adsorptive Separation of Propylene and Propane on a Porous Metal-Organic Framework, Copper Trimesate. Bull. Korean Chem. Soc. 2010, 31, 220-223. 61 Luo, F.; Yan, C. S.; Dang, L. L.; Krishna, R.; Zhou, W.; Wu, H.; Dong, X. L.; Han, Y.; Hu, T. L.; O’Keeffe, M.; Wang, L. L.; Luo, M. B.; Lin, R. B.; Chen, B. L. UTSA-74: A MOF-74 Isomer with Two Accessible Binding Sites per Metal Center for Highly Selective Gas Separation. J. Am. Chem. Soc. 2016, 138, 5678-5684. 62 Scott, H. S.; Shivanna, M.; Bajpai, A.; Madden, D. G.; Chen, K.-J.; Pham, T.; Forrest, K. A.; Hogan, A.; Space, B.; Perry IV, J. J.; Zaworotko, M. J. Highly Selective Separation of C2H2 from CO2 by a New Dichromate-Based Hybrid Ultramicroporous Material. ACS Appl. Mater. Interfaces 2017, 9, 33395-33400. 63 Wang, Y.; He, M.; Gao, X.; Li, S.; Xiong, S.; Krishna, R.; He, Y. Exploring the Effect of Ligand-Originated MOF Isomerism and Methoxy Group Functionalization on Selective Acetylene/Methane and Carbon Dioxide/Methane Adsorption Properties in Two NbO-Type MOFs. ACS Appl. Mater. Interfaces 2018, 10, 20559-20568. 64 Wu, L.; Yu, Z.; Ye, Y.; Yang, Y.; Zeng, H.; Huang, J.; Huang, Y.; Zhang, J.; Xiang, S. Sulfonated Periodic-Mesoporous-Organosilicas Column for Selective Separation of C2H2/CH4 Mixtures. J. Solid State Chem. 2018, 264, 113-118.


Page 14 of 15

Page 15 of 15 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


Table of Contents


Additive-Induced Supramolecular Isomerism and Enhancement of

Recommend Documents