共查询到20条相似文献,搜索用时 15 毫秒
1.
Dr. Jia Tang Mengke Cai Dr. Guanqun Xie Dr. Shixiong Bao Prof. Shujiang Ding Prof. Xiaoxia Wang Dr. Jinzhang Tao Prof. Guangqin Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4333-4340
With the assistance of hydrogen bonds of the o-amino group, we have successfully tuned a coordination structure from a metal–organic polyhedron (MOP) to a two-dimensional (2D) metal–organic framework (MOF). The amino group forms hydrogen bonds with the two vicinal carboxylic groups, and induces the ligand to coordinate with copper ions to form the 2D structure. The obtained 2D Cu-based MOF (Cu-AIA) has been applied as an efficient heterogeneous catalyst in the aerobic epoxidation of olefins by using air as oxygen source. Without the aggregation problem of active sites in MOPs, Cu-AIA possesses much higher reactivity than MOP-1. Furthermore, the amino group of the framework has been used as a modifiable site through post-synthetic metalation (PSMet) to prepare a 2D MOF-supported Pd single-site heterogeneous catalyst, which shows excellent catalytic performance for the Suzuki reaction. It indicates that Cu-AIA can also work as a good 2D MOF carrier for the derivation of other heterogeneous catalysts. 相似文献
2.
Dr. Yulia Yu. Enakieva Dr. Anna A. Sinelshchikova Prof. Mikhail S. Grigoriev Prof. Vladimir V. Chernyshev Dr. Konstantin A. Kovalenko Prof. Irina A. Stenina Prof. Andrey B. Yaroslavtsev Prof. Yulia G. Gorbunova Prof. Aslan Yu. Tsivadze 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(5):1598-1602
A novel metal–organic framework [Zn3(Ni-H2TPPP)(Ni-H4TPPP)(Ni-H5TPPP) ⋅ 7(CH3)2NH2 ⋅ DMF ⋅ 7 H2O] (where Ni-HxTPPP (x=2,4,5) are partially deprotonated [5,10,15,20-tetrakis(3-(phosphonatophenyl)-porphyrinato(2-))]nickel(II) species), IPCE-2Ni , with outstanding proton conductivity (1.0×10−2 S cm−1 at 75 °C and 95 % relative humidity) has been obtained. The high concentration of free phosphonate groups and compensating dimethylammonium cations bound by hydrogen bonds in the unique crystal structure of IPCE-2Ni is a key factor responsible for the observed high proton conductivity, which is one order of magnitude higher than for the corresponding MOF based on 5,10,15,20-tetrakis(4-(phosphonatophenyl)porphyrinato(2-))]nickel(II) IPCE-1Ni and comparable with that of leaders among MOFs. 相似文献
3.
Andrzej Gładysiak Dr. Tu N. Nguyen Dr. Mariana Spodaryk Dr. Jung-Hoon Lee Prof. Dr. Jeffrey B. Neaton Prof. Dr. Andreas Züttel Dr. Kyriakos C. Stylianou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(2):501-506
A pyrene-based metal-organic framework (MOF) SION-8 captured iodine (I2) vapor with a capacity of 460 and 250 mg g−1MOF at room temperature and 75 °C, respectively. Single-crystal X-ray diffraction analysis and van-der-Waals-corrected density functional theory calculations confirmed the presence of I2 molecules within the pores of SION-8 and their interaction with the pyrene-based ligands. The I2–pyrene interactions in the I2-loaded SION-8 led to a 104-fold increase of its electrical conductivity compared to the bare SION-8 . Upon adsorption, ≥95 % of I2 molecules were incarcerated and could not be washed out, signifying the potential of SION-8 towards the permanent capture of radioactive I2 at room temperature. 相似文献
4.
Dr. Ming Zhao Dr. Huilin Li Wei Li Junying Li Lingya Yi Dr. Weihua Hu Prof. Chang Ming Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17091-17096
An Ru-doping strategy is reported to substantially improve both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalytic activity of Ni/Fe-based metal–organic framework (MOF) for overall water splitting. As-synthesized Ru-doped Ni/Fe MIL-53 MOF nanosheets grown on nickel foam (MIL-53(Ru-NiFe)@NF) afford HER and OER current density of 50 mA cm−2 at an overpotential of 62 and 210 mV, respectively, in alkaline solution with a nominal Ru loading of ≈110 μg cm−2. When using as both anodic and cathodic (pre-)catalyst, MIL-53(Ru-NiFe)@NF enables overall water splitting at a current density of 50 mA cm−2 for a cell voltage of 1.6 V without iR compensation, which is much superior to state-of-the-art RuO2-Pt/C-based electrolyzer. It is discovered that the Ru-doping considerably modulates the growth of MOF to form thin nanosheets, and enhances the intrinsic HER electrocatalytic activity by accelerating the sluggish Volmer step and improving the intermediate oxygen adsorption for increased OER catalytic activity. 相似文献
5.
Amorphization of various solid materials has attracted increasing attentions. We report here an amorphization of metal–organic
framework-5 (MOF-5) of composition Zn4O(BDC)3 (BDC = 1,4-benzenedicarboxylate) using dielectric-barrier discharge (DBD) treatment at ambient pressure and low gas temperature
(around 120°C). The irreversible amorphization was confirmed by x-ray diffraction (XRD) characterization. The result of N2 adsorption–desorption measurements revealed a collapse of pores, which further supported the XRD results. The destroying
of part of carboxylate groups might be the main reason resulting in the amorphization of MOF-5. 相似文献
6.
Dr. Jun Liang Alexander Nuhnen Simon Millan Hergen Breitzke Vasily Gvilava Dr. Gerd Buntkowsky Prof. Dr. Christoph Janiak 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6124-6129
We present a facile approach to encapsulate functional porous organic cages (POCs) into a robust MOF by an incipient-wetness impregnation method. Porous cucurbit[6]uril (CB6) cages with high CO2 affinity were successfully encapsulated into the nanospace of Cr-based MIL-101 while retaining the crystal framework, morphology, and high stability of MIL-101. The encapsulated CB6 amount is controllable. Importantly, as the CB6 molecule with intrinsic micropores is smaller than the inner mesopores of MIL-101, more affinity sites for CO2 are created in the resulting CB6@MIL-101 composites, leading to enhanced CO2 uptake capacity and CO2/N2, CO2/CH4 separation performance at low pressures. This POC@MOF encapsulation strategy provides a facile route to introduce functional POCs into stable MOFs for various potential applications. 相似文献
7.
Shijie Xie Chaoyuan Deng Qing Huang Prof. Chuang Zhang Prof. Chuncheng Chen Prof. Jincai Zhao Prof. Hua Sheng 《Angewandte Chemie (International ed. in English)》2023,62(10):e202216717
Herein, we fabricated a π–π stacking hybrid photocatalyst by combining two two-dimensional (2D) materials: g-C3N4 and a Cu-porphyrin metal–organic framework (MOF). After an aerobic photocatalytic pretreatment, this hybrid catalyst exhibited an unprecedented ability to photocatalytically reduce CO2 to CO and CH4 under the typical level (20 %) of O2 in the air. Intriguingly, the presence of O2 did not suppress CO2 reduction; instead, a fivefold increase compared with that in the absence of O2 was observed. Structural analysis indicated that during aerobic pretreatment, the Cu node in the 2D-MOF moiety was hydroxylated by the hydroxyl generated from the reduction of O2. Then the formed hydroxylated Cu node maintained its structure during aerobic CO2 reduction, whereas it underwent structural alteration and was reductively devitalized in the absence of O2. Theoretical calculations further demonstrated that CO2 reduction, instead of O2 reduction, occurred preferentially on the hydroxylated Cu node. 相似文献
8.
Ashwini Jadhav Kriti Gupta Pranay Ninawe Prof. Dr. Nirmalya Ballav 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2235-2239
In this work, we have synthesized nanocomposites made up of a metal–organic framework (MOF) and conducting polymers by polymerization of specialty monomers such as pyrrole (Py) and 3,4-ethylenedioxythiophene (EDOT) in the voids of a stable and biporous Zr-based MOF ( UiO-66 ). FTIR and Raman data confirmed the presence of polypyrrole ( PPy ) and poly3,4-ethylenedioxythiophene ( PEDOT ) in UiO-66-PPy and UiO-66-PEDOT nanocomposites, respectively, and PXRD data revealed successful retention of the structure of the MOF. HRTEM images showed successful incorporation of polymer fibers inside the voids of the framework. Owing to the intrinsic biporosity of UiO-66 , polymer chains were observed to selectively occupy only one of the voids. This resulted in a remarkable enhancement (million-fold) of the electrical conductivity while the nanocomposites retain 60–70 % of the porosity of the original MOF. These semiconducting yet significantly porous MOF nanocomposite systems exhibited ultralow thermal conductivity. Enhanced electrical conductivity with lowered thermal conductivity could qualify such MOF nanocomposites for thermoelectric applications. 相似文献
9.
Yan Zhou Dr. Fei Yu Dr. Jian Su Prof. Dr. Mohamedally Kurmoo Prof. Dr. Jing-Lin Zuo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18922-18926
To activate electronic and optical functions of the redox-active metal–organic framework, (Me2NH2)[InIII(TTFTB)]⋅0.7 C2H5OH⋅DMF (Me2NH2@ 1 , TTFTB=tetrathiafulvalene-tetrabenzoate, DMF=N,N-dimethylformamide), has been exchanged by tetrathiafulvalenium (TTF.+) and N,N′-dimethyl-4,4′-bipyridinium (MV2+). These cations provide electron carriers and photosensitivity. The exchange retains the crystallinity allowing single-crystal to single-crystal post-synthetic transformation to TTF@ 1 and MV@ 1 . Both TTF.+ and MV2+ enhance the electrical conductivity by a factor of 102 and the visible light induced photocurrent by 4 and 28 times, respectively. EPR evidences synergetic effect involving charge transfer between the framework redox-active TTFTB bridges and MV2+. The results demonstrate that functionalization of MOF by cation exchange without perturbing the crystallinity extends possibilities to achieve switchable materials. 相似文献
10.
Zheng Wang Cheng-Yi Zhu Peng-Yan Fu Jun-Ting Mo Jia Ruan Prof. Mei Pan Prof. Cheng-Yong Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(33):7458-7462
Metal–organic frameworks (MOFs) with long persistent luminescence (LPL) have attracted widespread attention due to potential applications in displays, anticounterfeiting, and so on. However, MOFs often have large pore size, which restricts the formation of efficient inter- and intramolecular interactions to realize LPL. Herein, a new approach to achieving LPL in MOFs by multifold interpenetration of discrete frameworks is reported. By comparison between threefold- and twofold-interpenetrating MOFs, it was found that the former, which have higher multiplicity and denser frameworks, can be endowed with enhanced inter- and intramolecular interactions, and thus enhanced LPL is obtained. Meanwhile, metal-cluster and heavy-halogen effects could also cause variations in LPL duration and color. 相似文献
11.
Dr. Prantik Mondal Zachary Neuschuler Dr. Dipendu Mandal Ritchie E. Hernandez Prof. Seth M. Cohen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(9):e202317062
Postsynthetic modification (PSM) of metal–organic frameworks (MOFs) provides access to functional materials and advanced porous solid engineering. Herein, we report the reversible PSM of a multivariate isoreticular MOF by applying dynamic furan-maleimide Diels–Alder (DA) chemistry. The key step involves incorporating a furan group into the MOF via “click” PSM, which can then undergo repeated cycles of modification and de-modification with maleimides. The structural integrity, crystallinity, and porosity of the furan-appended MOF remained intact even after three consecutive PSM/de-modification cycles using three different functionalized maleimides. 相似文献
12.
Suhyun Ju Mohammad Yusuf Seongwan Jang Hyuntae Kang Soohee Kim Prof. Kang Hyun Park 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(33):7852-7859
Metal–organic framework (MOF)-based derivatives have been found to be promising heterogeneous catalysts for organic transformations. Herein, hollow-structure Cu-MOFs derived by reduction of Cu3(BTC)2 (BTC=1,3,5-benzenetricarboxylate; denoted as RCB) were prepared by using hydrazine hydrate as a reducing agent under various conditions. The influence of hydrazine hydrate induced the structure of Cu3(BTC)2 and led to dynamic variation in the interior and exterior as well as oxidation states of the Cu ion. The synthesized materials were characterized by SEM, TEM, N2 sorption isotherms, XRD, and XPS. The product of the catalytic reaction was observed by GC-MS. In addition, the prepared RCBs were found to have excellent catalytic activity and selectivity for benzyl alcohol oxidation when assisted by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO). 相似文献
13.
Lei Hu Tuzhi Xiong Ran Liu Yuwen Hu Dr. Yanchao Mao Prof. M.-Sadeeq Balogun Prof. Yexiang Tong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(26):6575-6583
In the work reported herein, the electrocatalytic properties of Co3O4 in hydrogen and oxygen evolution reactions have been significantly enhanced by coating a shell layer of a copper-based metal–organic framework on Co3O4 porous nanowire arrays and using the products as high-performance bifunctional electrocatalysts for overall water splitting. The coating of the copper-based metal–organic framework resulted in the hybridization of the copper-embedded protective carbon shell layer with Co3O4 to create a strong Cu−O−Co bonding interaction for efficient hydrogen adsorption. The hybridization also led to electronically induced oxygen defects and nitrogen doping to effectively enhance the electrical conductivity of Co3O4. The optimal as-prepared core–shell hybrid material displayed excellent overall-water-splitting catalytic activity that required overall voltages of 1.45 and 1.57 V to reach onset and a current density of 10 mA cm−2, respectively. This is the first report to highlight the relevance of hybridizing MOF-based co-catalysts to boost the electrocatalytic performance of nonprecious transition-metal oxides. 相似文献
14.
Dr. Lauren N. McHugh Michael F. Thorne Georgina Robertson Dr. Giorgio Divitini Dr. Thomas D. Bennett 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(7):e202104026
The formation, and subsequent structural, thermal and adsorptive properties of single-component metal–organic framework crystal-glass composites (MOF-CGCs) are investigated. A series of novel materials exhibiting chemically identical glassy and crystalline phases within the same material were produced, where crystalline ZIF-62(Zn) was incorporated within an agZIF-62(Zn) matrix. X-ray diffraction showed that the crystalline phase was still present after heating to above the glass transition temperature of agZIF-62(Zn), and interfacial compatibility between the crystalline and glassy phases was investigated using a mixed-metal (ZIF-62(Co))0.5(agZIF-62(Zn))0.5 analogue. CO2 gas adsorption measurements showed that the CO2 uptakes of the MOF-CGCs were between those of the crystalline and glassy phases. 相似文献
15.
Yi-Da Song Wei Huan Ho Yu-Chuan Chen Jun-Hong Li Yi-Sen Wang Yu-Juan Gu Cheng-Hsun Chuang Prof. Chung-Wei Kung 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3560-3567
In this study, a strategy that can result in the polyaniline (PANI) solely confined within the nanopores of a metal–organic framework (MOF) without forming obvious bulk PANI between MOF crystals is developed. A water-stable zirconium-based MOF, UiO-66-NH2, is selected as the MOF material. The polymerization of aniline is initiated in the acidic suspension of UiO-66-NH2 nanocrystals in the presence of excess poly(sodium 4-styrenesulfonate) (PSS). Since the pore size of UiO-66-NH2 is too small to enable the insertion of the bulky PSS, the quick formation of pore-confined solid PANI and the slower formation of well dispersed PANI:PSS occur within the MOF crystals and in the bulk solution, respectively. By taking advantage of the resulting homogeneous PANI:PSS polymer solution, the bulk PANI:PSS can be removed from the PANI/UiO-66-NH2 solid by successive washing the sample with fresh acidic solutions through centrifugation. As this is the first time reporting the PANI solely confined in the pores of a MOF, as a demonstration, the obtained PANI/UiO-66-NH2 composite material is applied as the electrode material for supercapacitors. The PANI/UiO-66-NH2 thin films exhibit a pseudocapacitive electrochemical characteristic, and their resulting electrochemical activity and charge-storage capacities are remarkably higher than those of the bulk PANI thin films. 相似文献
16.
Julia G. Knapp Dr. Xijun Wang Dr. Andrew S. Rosen Xingjie Wang Dr. Xinyi Gong Dr. Matthew Schneider Dr. Tatyana Elkin Dr. Kent O. Kirlikovali Dr. Melissa Fairley Dr. Matthew D. Krzyaniak Prof. Michael R. Wasielewski Prof. Nathan C. Gianneschi Prof. Randall Q. Snurr Prof. Omar K. Farha 《Angewandte Chemie (International ed. in English)》2023,62(29):e202305526
The interactions between uranium and non-innocent organic species are an essential component of fundamental uranium redox chemistry. However, they have seldom been explored in the context of multidimensional, porous materials. Uranium-based metal–organic frameworks (MOFs) offer a new angle to study these interactions, as these self-assembled species stabilize uranium species through immobilization by organic linkers within a crystalline framework, while potentially providing a method for adjusting metal oxidation state through coordination of non-innocent linkers. We report the synthesis of the MOF NU-1700 , assembled from U4+-paddlewheel nodes and catecholate-based linkers. We propose this highly unusual structure, which contains two U4+ ions in a paddlewheel built from four linkers—a first among uranium materials—as a result of extensive characterization via powder X-ray diffraction (PXRD), sorption, transmission electron microscopy (TEM), and thermogravimetric analysis (TGA), in addition to density functional theory (DFT) calculations. 相似文献
17.
Sheela Thapa Lingyao Meng Dr. Eshani Hettiarachchi Yousef K. Bader Dr. Diane A. Dickie Dr. Gayan Rubasinghege Dr. Sergei A. Ivanov Dr. Erika C. Vreeland Prof. Dr. Yang Qin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13788-13791
Charge-separated metal–organic frameworks (MOFs) are a unique class of MOFs that can possess added properties originating from the exposed ionic species. A new charge-separated MOF, namely, UNM-6 synthesized from a tetrahedral borate ligand and Co2+ cation is reported herein. UNM-6 crystalizes into the highly symmetric P43n space group with fourfold interpenetration, despite the stoichiometric imbalance between the B and Co atoms, which also leads to loosely bound NO3− anions within the crystal structure. These NO3− ions can be quantitatively exchanged with various other anions, leading to Lewis acid (Co2+) and Lewis base (anions) pairs within the pores and potentially cooperative catalytic activities. For example, UNM-6-Br, the MOF after anion exchange with Br− anions, displays high catalytic activity and stability in reactions of CO2 chemical fixation into cyclic carbonates. 相似文献
18.
Muhammad Ibrar Ahmed Dr. Chuangwei Liu Dr. Yong Zhao Dr. Wenhao Ren Dr. Xianjue Chen Dr. Sheng Chen Prof. Chuan Zhao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(48):21649-21653
Inspired by the metal–sulfur (M-S) linkages in the nitrogenase enzyme, here we show a surface modification strategy to modulate the electronic structure and improve the N2 availability on a catalytic surface, which suppresses the hydrogen evolution reaction (HER) and improves the rate of NH3 production. Ruthenium nanocrystals anchored on reduced graphene oxide (Ru/rGO) are modified with different aliphatic thiols to achieve M-S linkages. A high faradaic efficiency (11 %) with an improved NH3 yield (50 μg h−1 mg−1) is achieved at −0.1 V vs. RHE in acidic conditions by using dodecanethiol. DFT calculations reveal intermediate N2 adsorption and desorption of the product is achieved by electronic structure modification along with the suppression of the HER by surface modification. The modified catalyst shows excellent stability and recyclability for NH3 production, as confirmed by rigorous control experiments including 15N isotope labeling experiments. 相似文献
19.
Development of Highly Effective Nanoparticle Spinel Catalysts for Aerobic Oxidation of Benzylic Alcohols 总被引:2,自引:0,他引:2
Selectiveoxidationofalcoholshasbeenwidelystud iedduetoitsimportanceinmanyorganicsyntheses .1 7Howtomakemoreeffective ,cheap ,easilyaccessibleandenvironmentallybenigncatalystsismatterofwideinter est .Itiswellknownthatspinel type (AB2 O4 )ofcom plexoxidescanbeapp… 相似文献
20.
Dr. Jingfang Zhang Dr. Wenzhe Li Dr. Yafei Qi Dr. Guorong Wang Prof. Lele Li Prof. Zhengyu Jin Prof. Jie Tian Prof. Yang Du 《Angewandte Chemie (International ed. in English)》2023,62(5):e202214750
Immune checkpoint blockade has become a paradigm-shifting treatment modality to combat cancer, while conventional administration of immune checkpoint inhibitors, such as anti-PD-L1 antibody (α-PD-L1), often shows unsatisfactory immune responses and lead to severe immune-related adverse effects (irAEs). Herein, we develop a PD-L1 aptamer-based spherical nucleic acids (SNAs), which consists of oxaliplatin (OXA) encapsulated in a metal–organic framework nanoparticle core and a dense shell of aptPD-L1 (denoted as M@O-A). Upon light irradiation, this nanosystem enables concurrent photodynamic therapy (PDT), chemotherapy, and enhanced immunotherapy in one shot to inhibit both primary colorectal tumors and untreated distant tumors in mice. Notably, M@O-A shows scarcely any systemic immunotoxicity in a clinical irAEs-mimic transgenic mouse model. Collectively, this study presents a novel strategy for priming robust photo-immunotherapy against cancer with enhanced safety. 相似文献