Ultrahigh‐Uptake Capacity‐Enabled Gas Separation and Fruit Preservation by a New Single‐Walled Nickel–Organic Framework

Abstract

High gas‐uptake capacity is desirable for many reasons such as gas storage and sequestration. Moreover, ultrahigh capacity can enable a practical separation process by mitigating the selectivity factor that sometimes compromises separation efficiency. Herein, a single‐walled nickel–organic framework with an exceptionally high gas capture capability is reported. For example, C2H4 and C2H6 uptake capacities are at record‐setting levels of 224 and 289 cm3 g−1 at 273 K and 1 bar (169 and 110 cm3 g−1 at 298 K and 1 bar), respectively. Such ultrahigh capacities for both gases give rise to an excellent separation performance, as shown for C2H6/C2H4 with breakthrough times of 100, 60 and 30 min at 273, 283 and 298 K and under 1 atm. This new material is also shown to readily remove ethylene released from fruits, and once again, its ultrahigh capacity plays a key role in the extraordinary length of time achieved in the preservation of the fruit freshness.

Improving Ethane/Ethylene Separation Performance of Isoreticular Metal–Organic Frameworks via Substituent Engineering

“…Under the conditions of 298 K and 109 kPa, the adsorption selectivity of C 2 H 6 over C 2 H 4 , respectively, reaches 1.7, 1.4, 1.3, and 1.2 for ZJNU-21 , NJU-Bai7 , ZJNU-22 , and ZJNU-23 . The selectivity value of ZJNU-21 is similar to and even surpasses that of many coordination framework compounds reported for C 2 H 6 /C 2 H 4 separation (Figure g), such as MUF-15 (1.95), DUT-52­(Hf) (1.9), PCN-250 (1.9), NUM-7 (1.764), Dia-4-Ni (1.76), Ca­(H 2 tcpb) (1.67), CPM-233 (1.64), NUM-9 (1.61), JNU-2 (1.6), SNNU-40 (1.58), LIFM-63 (1.56), JXNU-9 (1.53), MIL-53-NDCA (1.53), Sc-BPDC (1.5), MIL-142A (1.5), Azole-Th-1 (1.44), UPC-612 (1.41), In- soc -MOF-1 (1.4), NPU-1 (1.32), MOF-545 (1.31), and CPOC-301 (1.3), but is inferior to that of a few high-performance C 2 H 6 -selective coordination framework compounds like Fe 2 O 2 (dobdc) (4.4), Cu­(Qc) 2 (3.4), Co­(AIN) 2 (2.96), ZJU-120 (2.74), MAF-49 (2.7), and NKMOF-8-Br (2.65) . As shown in Figures S26–S29, the adsorption selectivity of C 2 H 6 over C 2 H 4 increases with the decreasing measurement temperatures.…”

“…At the temperature of 298 K, the K H values of C 2 H 6 and C 2 H 4 are 0.344 and 0.239 mmol g −1 kPa −1 for NJU-Bai7 (Figure S18), 0.503 and 0.338 mmol g −1 kPa −1 for ZJNU-21 (Figure S19), 0.322 and 0.254 mmol g −1 kPa −1 for ZJNU-22 (Figure S20), and 0.467 and 0.403 mmol g −1 kPa −1 for ZJNU-23 (Figure S21), respectively. 4g), such as MUF-15 (1.95), 38 DUT-52(Hf) (1.9), 33 PCN-250 (1.9), 39 NUM-7 (1.764), 40 Dia-4-Ni (1.76), 34 Ca(H 2 tcpb) (1.67), 41 CPM-233 (1.64), 42 NUM-9 (1.61), 43 JNU-2 (1.6), 44 SNNU-40 (1.58), 45 LIFM-63 (1.56), 46 JXNU-9 (1.53), 47 MIL-53-NDCA (1.53), 48 Sc-BPDC (1.5), 49 MIL-142A (1.5), 50 Azole-Th-1 (1.44), 51 UPC-612 (1.41), 52 In-soc-MOF-1 (1.4), 53 NPU-1 (1.32), 54 MOF-545 (1.31), 55 and CPOC-301 (1.3), 56 but is inferior to that of a few high-performance C 2 H 6 -selective coordination framework compounds like Fe 2 O 2 (dobdc) (4.4), 36 Cu(Qc) 2 (3.4), 57 Co(AIN) 2 (2.96), 30 ZJU-120 (2.74), 58 MAF-49 (2.7), 29 and NKMOF-8-Br (2.65). 59 As shown in Figures S26−S29, the adsorption selectivity of C 2 H 6 over C 2 H 4 increases with the decreasing measurement temperatures.…”

Bottom-Up Synthesis of 8-Connected Three-Dimensional Covalent Organic Frameworks for Highly Efficient Ethylene/Ethane Separation

“…It should be noted that the C 2 H 6 uptake for NKCOF - 21 was higher than all reported C 2 H 6 -selective COFs ( COF - 1 , - 6 , - 8 , - 10 , - 102 , - 300 , - 320 , MCOF - 1 , DBA - 3D - COF - 1 , , and Ni - DBA - 3D - COF ) and some traditional porous materials ( Kureha carbon , SFZ8C - 700 , zeolite SOF , zeolite OBW , and silicalite - 1 ) but lower than some top-performance C 2 H 6 -selective MOFs such as Ni ( bdc )­( ted ) 0 . 5 , PCN - 250 , IRMOF - 8 , ZJU - 120a , SNNU - 40 , and CPMs Figure e and Table S4).…”

“…Moreover, the produced C 2 H 4 is often of low purity owing to the coadsorption of C 2 H 4 and C 2 H 6 . (ii) C 2 H 6 -selective adsorbents show an obvious advantage over C 2 H 4 -selective adsorbents, that is, capable of directly harvesting pure C 2 H 4 through a single adsorption process, greatly simplifying the separation process and saving ∼40% energy consumption . Therefore, developing new types of C 2 H 6 -selective adsorbents with superb ethane/ethylene separation performances and high durability is highly desired for the industrial purification of C 2 H 4 .…”

From Co-MOF to CoNi-MOF to Ni-MOF: A Facile Synthesis of 1D Micro-/Nanomaterials

“…Metal–organic frameworks (MOFs), also known as porous coordination polymers, are crystalline materials that are constructed by alternative connecting metal ions/clusters with organic linkers. − This class of materials have attracted enormous attention in various fields such as gas sorption, − separation, , and catalysis − owing to their intriguing features including diverse compositions, extraordinary high surface area, ordered pore structures, , and easy tailorable chemistry . However, MOFs are usually bulk-scale hybrid materials that some weaknesses such as poor chemical stability and electrical conductivity will prevent their full use.…”