Constructing stable palladium(II)-based metal–organic frameworks (MOFs) would unlock more opportunities for MOF chemistry, particularly toward applications in catalysis. However, their availability ...is limited by synthetic challenges due to the inertness of the Pd–ligand coordination bond, as well as the strong tendency of the Pd(II) source to be reduced under typical solvothermal conditions. Under the guidance of reticular chemistry, herein, we present the first example of an azolate Pd-MOF, BUT-33(Pd), obtained via a deuterated solvent-assisted metal metathesis. BUT-33(Pd) retains the underlying sodalite network and mesoporosity of the template BUT-33(Ni) and shows excellent chemical stability (resistance to an 8 M NaOH aqueous solution). With rich Pd(II) sites in the atomically precise distribution, it also demonstrates good performances as a heterogeneous Pd(II) catalyst in a wide application scope, including Suzuki/Heck coupling reactions and photocatalytic CO2 reduction to CH4. This work highlights a feasible approach to reticularly construct noble metal based MOFs via metal metathesis, in which various merits, including high chemical stability, large pores, and tunable functions, have been integrated for addressing challenging tasks.
In principle, porous physisorbents are attractive candidates for the removal of volatile organic compounds such as benzene by virtue of their low energy for the capture and release of this pollutant. ...Unfortunately, many physisorbents exhibit weak sorbate-sorbent interactions, resulting in poor selectivity and low uptake when volatile organic compounds are present at trace concentrations. Herein, we report that a family of double-walled metal-dipyrazolate frameworks, BUT-53 to BUT-58, exhibit benzene uptakes at 298 K of 2.47-3.28 mmol g
at <10 Pa. Breakthrough experiments revealed that BUT-55, a supramolecular isomer of the metal-organic framework Co(BDP) (H
BDP = 1,4-di(1H-pyrazol-4-yl)benzene), captures trace levels of benzene, producing an air stream with benzene content below acceptable limits. Furthermore, BUT-55 can be regenerated with mild heating. Insight into the performance of BUT-55 comes from the crystal structure of the benzene-loaded phase (C
H
@BUT-55) and density functional theory calculations, which reveal that C-H···X interactions drive the tight binding of benzene. Our results demonstrate that BUT-55 is a recyclable physisorbent that exhibits high affinity and adsorption capacity towards benzene, making it a candidate for environmental remediation of benzene-contaminated gas mixtures.
Metal-organic frameworks (MOFs) have emerged as one of the most fascinating libraries of porous materials. In spite of their myriad merits, practical application of most MOFs is restricted due to ...their high preparation cost because of the complicated organic ligands involved. To address this limitation, we propose to use simple and cheap organic precursors to synthesize MOFs with complicated ligands
"one-pot"
reactions of these precursors along with the formation of new MOFs. In this work, we have carefully screened several organic reactions, through which target ligands were generated
from easily available reactants during the MOF construction. With this "one-pot" approach, the fabrication of a series of novel MOFs by integrating the organic covalent bond and the coordinate bond has thus been realized through the judicious selection of organic reactions, which effectively simplifies the MOF synthesis process and thus reduces the cost.
Benzene and SO2, coexisting as hazardous air pollutants in some cases, such as in coke oven emissions, have led to detrimental health and environmental effects. Physisorbents offer promise in ...capturing benzene and SO2, while their performance compromises at low concentration. Particularly, the simultaneous capture of trace benzene and SO2 under humid conditions is attractive but challenging. Here, we address this issue by constructing a robust pyrazolate metal-organic framework (MOF) sorbent featuring rich accessible Ni(II) sites with low affinity to water and good stability. This material achieves a high benzene uptake of 5.08 mmol g–1 at 10 Pa, surpassing previous benchmarks. More importantly, it exhibits an adsorption capacity of ~0.51 mmol g–1 for 10 ppm benzene and ~1.21 mmol g–1 for 250 ppm SO2 under 30% relative humidity. This work demonstrates that a pioneering MOF enables simultaneous capture of trace benzene and SO2, highlighting the potential of physisorbents for industrial effluent remediation, even in the presence of moisture.Benzene and SO2 coexist as hazardous air pollutants. Here the authors synthesized a robust pyrazolate MOF sorbent with accessible Ni(II) sites that can simultaneously capture trace amounts of benzene and SO2 under humid conditions.
Nonplanar porphyrins play crucial roles in many biological processes and chemical reactions as catalysts. However, the preparation of artificial nonplanar porphyrins suffers from complicated organic ...syntheses. Herein, we present a new rare-earth porphyrinic metal–organic framework (RE-PMOF), BUT-233, which is a three-dimensional (3D) framework structure with the flu topology consisting of 4-connected BBCPPP-Ph ligands H4BBCPPP-Ph = 5′,5⁗-(10,20-diphenylporphyrin-5,15-diyl)bis(1,1′:3′,1″-terphenyl-4,4′′ dicarboxylic acid) and 8-connected Eu6 clusters. Noteworthily, the porphyrin cores of the BBCPPP-Ph ligands in BUT-233 are nonplanar with a ruffle-like conformation. In contrast, the porphyrin core in the free ligand H4BBCPPP-Ph is in a nearly ideally planar conformation, as confirmed by its single-crystal structure. BUT-233 is microporous with 6–8 Å pores and a Brunauer–Emmett–Teller (BET) surface area of 649 m2/g, as well as high stability in common solvents. The MOF was used as a photocatalyst for the oxidation degradation of a chemical warfare agent model molecule CEES (CEES = 2-chloroethyl ethyl sulfide) under the light-emitting diode (LED) irradiation and an O2 atmosphere at room temperature. CEES was almost completely converted into its nontoxic light-oxidized product CEESO (CEESO = 2-chloroethyl ethyl sulfoxide) in only 5 min with t 1/2 = 2 min (t 1/2: half-life). Moreover, the toxic deep-oxidized product 2-chloroethyl ethyl sulfone (CEESO2) was not detected. The catalytic activity of BUT-233 was high in comparison with those of some previously reported MOF catalysts. The results of photo/electrochemical property studies suggested that the high catalytic activity of BUT-233 was benefited from the presence of nonplanar porphyrin rings on its pore surface.
Aim
To avoid complications associated with uterine compression sutures, we devised a ring compression suture (RCS).
Methods
The RCS was performed on 12 patients with post‐partum hemorrhage (PPH) ...during cesarean section. The suture was inserted 0.5 cm below the attachment point of the uterosacral ligament into the uterine cavity and pushed downward through the cervical canal into the vagina. The other end of the stitch was threaded through the lower abdominal wall, from the inside of the abdomen cavity to the outside of the abdominal wall, emerging at the external surface of the lower abdomen 2 cm lateral to the ventral median line and 1 cm above the symphysis pubis. Then, the two ends of the suture (the end in the vagina had been pulled out in advance) were tied tightly on the pudendum. The same stitch was repeated on the contralateral side. After 48 h postoperatively, the suture was removed through the vagina under sterilization.
Results
All 12 women with PPH who underwent RCS achieved hemostasis, and complications related to RCS were not seen. Two of them had successful pregnancies postoperatively. The remaining women had no desire for a further pregnancy.
Conclusion
The procedure can be used as an alternative to peripartum hysterectomy and also as a prophylactic application in PPH.
Expanding the structural diversity of porphyrinic metal–organic frameworks (PMOFs) is essential to develop functional materials with novel properties or enhanced performance in different ...applications. Herein, we establish a strategy to construct rare-earth (RE) PMOFs with unprecedented topology via rational functionalization of porphyrinic ligands. By introducing phenyl/pyridyl groups to the meso-positions of the porphyrin core, the symmetries and connectivities of the ligands are tuned, and three RE-PMOFs (BUT-224/-225/-226) with new topologies are successfully obtained. In addition, BUT-225(Co), with both the Lewis basic and acidic sites, exhibits enhanced CO2 uptake and higher catalytic activity for the cycloaddition of CO2 and epoxides under mild conditions. This work reveals that the RE-PMOFs with novel topologies can be rationally designed and constructed through ligand functionalization, which provides insights into the construction of tailored PMOFs for various applications.
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•A facile mixed-ligand approach is adopted to functionalize IRMOF-74-IV with metalloporphyrin for multivariate mesoporous analogs.•Compared with IRMOF-74-IV, the functionalized ...analogs show improved stability and performance in photocatalytic CO2 reduction.•The photocatalytic performance of IRMOF-74-IV analogs could be optimized by tuning the contents and species of metalloporphyrin.
Metal-organic frameworks (MOFs) are widely employed as functional materials in various fields, while intriguing properties for specific applications have been pursued all along with their development. Herein, we adopt a ligand substitution strategy to functionalize the mesoporous IRMOF-74-IV for multivariate MOF catalysts. With similar size and geometry, the porphyrin ligand 4,4′-(porphyrin-5,15-diyl)bis(2-hydroxybenzolate) (PBHB2–) was mixed with the 3,3′″-dihydroxy-2′,2″,5′,5″-tetramethyl-1,1′:4′,1″:4″,1″′-quaterphenyl-4,4″′-dicarboxylate (L-IV2–) ligand in synthesis, giving porphyrin functionalized IRMOF-74-IV analogs. Compared with IRMOF-74-IV, the IRMOF-74-IV-PBHBX-M series show improved stability and performance in photocatalytic CO2 reduction. After tuning the contents of porphyrin ligand and the species of metal ion, IRMOF-74-IV-PBHB45%-Cu demonstrates to be the best as an efficient photocatalyst for the CO2-to-CO conversion. This work has achieved to tailor extant MOFs through a mixed-ligand approach, which would contribute to more multivariate materials and unlock new opportunities for their applications.
Optimizing Hadoop with the parameter tuning is an effective way to greatly improve the performance, but it usually costs too much time to identify the optimal parameters configuration because there ...are many parameters. Users are always blindly adjust too many parameters and are sometimes confused about which one could be changed at a higher-priority. To make optimization easier, classifying the parameter based on different applications will be helpful. In this paper, we will introduce a method that can classify these parameters in order that users can optimize performance more quickly and effectively for different applications.
Rare-earth metal–organic frameworks (RE-MOFs), which are composed of polynuclear RE clusters of high connection, are gaining prominent attention in MOF chemistry, due to their tremendous structure ...diversity. The vulnerability of RE-MOFs to moisture and acid/alkaline conditions, however, has limited their modification and application. Herein, based on MOF reticular chemistry, we utilize a ditopic linker of distinct spatial configuration to construct a series of RE(III)-MOFs with bcu topology, BUT-47(M) (M = Tb3+, Y3+, Yb3+ and Tm3+; BUT = Beijing University of Technology), featuring the rare 8-connected RE6 clusters and defective sites. BUT-47(Tb) shows high chemical stability in a wide pH range (2–12). The functionalized BUT-47(Tb) through post-modification in the defective RE6 clusters demonstrates to be capable of selective fluorescence detection of hydrogen peroxide. This work not only highlights the strength of reticular chemistry principles in designing stable RE-MOFs with intriguing structures but also offers smart platforms to tailor properties for specific applications.
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