I11-High Resolution Powder Diffraction
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Zi
Wang
,
Alena M.
Sheveleva
,
Daniel
Lee
,
Yinlin
Chen
,
Dinu
Iuga
,
W. Trent
Franks
,
Yujie
Ma
,
Jiangnan
Li
,
Lei
Li
,
Yongqiang
Cheng
,
Luke L.
Daemen
,
Sarah J.
Day
,
Anibal J.
Ramirez-Cuesta
,
Bing
Han
,
Alexander S.
Eggeman
,
Eric J. L.
Mcinnes
,
Floriana
Tuna
,
Sihai
Yang
,
Martin
Schroeder
Abstract: We report the modulation of reactivity of nitrogen dioxide (NO2) in a charged metal-organic framework (MOF) material, MFM-305-CH3 in which unbound N-centres are methylated and the cationic charge counter-balanced by Cl− ions in the pores. Uptake of NO2 into MFM-305-CH3 leads to reaction between NO2 and Cl– to give nitrosyl chloride (NOCl) and NO3− anions. A high dynamic uptake of 6.58 mmol g−1 at 298 K is observed for MFM-305-CH3 as measured using a flow of 500 ppm NO2 in He. In contrast, the analogous neutral material, MFM-305, shows a much lower uptake of 2.38 mmol g−1. The binding domains and reactivity of adsorbed NO2 molecules within MFM-305-CH3 and MFM-305 have been probed using in situ synchrotron X-ray diffraction, inelastic neutron scattering and by electron paramagnetic resonance, high-field solid-state nuclear magnetic resonance and UV-vis spectroscopies. The design of charged porous sorbents provides a new platform to control the reactivity of corrosive air pollutants.
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Apr 2023
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B22-Multimode InfraRed imaging And Microspectroscopy
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Lixia
Guo
,
Joseph
Hurd
,
Meng
He
,
Wanpeng
Lu
,
Jiangnan
Li
,
Danielle
Crawshaw
,
Mengtian
Fan
,
Sergey A.
Sapchenko
,
Yinlin
Chen
,
Xiangdi
Zeng
,
Meredydd
Kippax-Jones
,
Wenyuan
Huang
,
Zhaodong
Zhu
,
Pascal
Manuel
,
Mark D.
Frogley
,
Daniel
Lee
,
Martin
Schroeder
,
Sihai
Yang
Diamond Proposal Number(s):
[30398]
Open Access
Abstract: The development of stable sorbent materials to deliver reversible adsorption of ammonia (NH3) is a challenging task. Here, we report the efficient capture and storage of NH3 in a series of robust microporous aluminium-based metal-organic framework materials, namely MIL-160, CAU-10-H, Al-fum, and MIL-53(Al). In particular, MIL-160 shows high uptakes of NH3 of 4.8 and 12.8 mmol g−1 at both low and high pressure (0.001 and 1.0 bar, respectively) at 298 K. The combination of in situ neutron powder diffraction, synchrotron infrared micro-spectroscopy and solid-state nuclear magnetic resonance spectroscopy reveals the preferred adsorption domains of NH3 molecules in MIL-160, with H/D site-exchange between the host and guest and an unusual distortion of the local structure of [AlO6] moieties being observed. Dynamic breakthrough experiments confirm the excellent ability of MIL-160 to capture of NH3 with a dynamic uptake of 4.2 mmol g−1 at 1000 ppm. The combination of high porosity, pore aperture size and multiple binding sites promotes the significant binding affinity and capacity for NH3, which makes it a promising candidate for practical applications.
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Mar 2023
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B22-Multimode InfraRed imaging And Microspectroscopy
I11-High Resolution Powder Diffraction
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Yu
Han
,
Yinlin
Chen
,
Yujie
Ma
,
Jamie
Bailey
,
Zi
Wang
,
Daniel
Lee
,
Alena M.
Sheveleva
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Mark D.
Frogley
,
Sarah J.
Day
,
Stephen P.
Thompson
,
Ben F.
Spencer
,
Marek
Nikiel
,
Pascal
Manuel
,
Danielle
Crawshaw
,
Martin
Schroeder
,
Sihai
Yang
Diamond Proposal Number(s):
[30398]
Open Access
Abstract: Benzene is an important air pollutant and a key chemical feedstock for the synthesis of cyclohexane. Because of the small difference of 0.6°C in their boiling points, the separation of benzene and cyclohexane is extremely challenging. Here, we report the high adsorption of benzene at low pressure and efficient separation of benzene/cyclohexane, achieved by the control of pore chemistry of two families of robust metal-organic frameworks, UiO-66 and MFM-300. At 298 K, UiO-66-CuII shows an exceptional adsorption of benzene of 3.92 mmol g−1 at 1.2 mbar and MFM-300(Sc) exhibits a high selectivity of 166 for the separation of benzene/cyclohexane (v/v = 1/1) mixture. In situ synchrotron X-ray diffraction and neutron powder diffraction, and multiple spectroscopic techniques reveal the binding mechanisms of benzene and cyclohexane in these materials. We also report the first example of direct visualization of reversible binding of benzene at an open Cu(II) site within metal-organic frameworks.
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Feb 2023
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I11-High Resolution Powder Diffraction
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Jiangnan
Li
,
Zi
Wang
,
Yinlin
Chen
,
Yongqiang
Cheng
,
Luke L.
Daemen
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Sarah J.
Day
,
Anibal J.
Ramirez-Cuesta
,
Martin
Schroeder
,
Sihai
Yang
Diamond Proposal Number(s):
[31365]
Open Access
Abstract: Increasing levels of air pollution are driving the need for the development of new processes that take “waste-to-chemicals”. Herein, we report the capture and conversion under ambient conditions of a major air pollutant, NO2, using a robust metal-organic framework (MOF) material, Zr-bptc (H4bptc = 3,3′,5,5′-biphenyltetracarboxylic acid), comprising {Zr6(μ3-O)4(μ3-OH)4(COO)12} clusters linked by 4-connected bptc4– ligands in an ftw topology. At 298 K, Zr-bptc shows exceptional stability and adsorption of NO2 at both low (4.9 mmol g–1 at 10 mbar) and high pressures (13.8 mmol g–1 at 1.0 bar), as measured by isotherm experiments. Dynamic breakthrough experiments have confirmed the selective retention of NO2 by Zr-bptc at low concentrations under both dry and wet conditions. The immobilized NO2 can be readily transformed into valuable nitro compounds relevant to construction, agrochemical, and pharmaceutical industries. In situ crystallographic and spectroscopic studies reveal strong binding interactions of NO2 to the {Zr6(μ3-O)4(μ3-OH)4(COO)12} cluster node. This study paves a circular pathway to enable the integration of nitrogen-based air pollutants into the production of fine chemicals.
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Oct 2022
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B18-Core EXAFS
B22-Multimode InfraRed imaging And Microspectroscopy
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Yujie
Ma
,
Wanpeng
Lu
,
Xue
Han
,
Yinlin
Chen
,
Ivan
Da Silva
,
Daniel
Lee
,
Alena M.
Sheveleva
,
Zi
Wang
,
Jiangnan
Li
,
Weiyao
Li
,
Mengtian
Fan
,
Shaojun
Xu
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Yongqiang
Cheng
,
Svemir
Rudic
,
Pascal
Manuel
,
Mark D.
Frogley
,
Anibal J.
Ramirez-Cuesta
,
Martin
Schroeder
,
Sihai
Yang
Diamond Proposal Number(s):
[19850]
Open Access
Abstract: The presence of active sites in metal–organic framework (MOF) materials can control and affect their performance significantly in adsorption and catalysis. However, revealing the interactions between the substrate and active sites in MOFs at atomic precision remains a challenging task. Here, we report the direct observation of binding of NH3 in a series of UiO-66 materials containing atomically dispersed defects and open Cu(I) and Cu(II) sites. While all MOFs in this series exhibit similar surface areas (1111–1135 m2 g–1), decoration of the −OH site in UiO-66-defect with Cu(II) results in a 43% enhancement of the isothermal uptake of NH3 at 273 K and 1.0 bar from 11.8 in UiO-66-defect to 16.9 mmol g–1 in UiO-66-CuII. A 100% enhancement of dynamic adsorption of NH3 at a concentration level of 630 ppm from 2.07 mmol g–1 in UiO-66-defect to 4.15 mmol g–1 in UiO-66-CuII at 298 K is observed. In situ neutron powder diffraction, inelastic neutron scattering, and electron paramagnetic resonance, solid-state nuclear magnetic resonance, and infrared spectroscopies, coupled with modeling reveal that the enhanced NH3 uptake in UiO-66-CuII originates from a {Cu(II)···NH3} interaction, with a reversible change in geometry at Cu(II) from near-linear to trigonal coordination. This work represents the first example of structural elucidation of NH3 binding in MOFs containing open metal sites and will inform the design of new efficient MOF sorbents by targeted control of active sites for NH3 capture and storage.
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May 2022
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B22-Multimode InfraRed imaging And Microspectroscopy
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Lixia
Guo
,
Xue
Han
,
Yujie
Ma
,
Jiangnan
Li
,
Wanpeng
Lu
,
Weiyao
Li
,
Daniel
Lee
,
Ivan
Da Silva
,
Yongqiang
Cheng
,
Svemir
Rudic
,
Pascal
Manuel
,
Mark D.
Frogley
,
Anibal Javier
Ramirez-Cuesta
,
Martin
Schroeder
,
Sihai
Yang
Diamond Proposal Number(s):
[30398]
Open Access
Abstract: To understand the exceptional adsorption of ammonia (NH3) in MFM-300(Sc) (19.5 mmol g−1 at 273 K and 1 bar without hysteresis), we report a systematic investigation of the mechanism of adsorption by a combination of in situ neutron powder diffraction, inelastic neutron scattering, synchrotron infrared microspectroscopy, and solid-state 45Sc NMR spectroscopy. These complementary techniques reveal the formation of reversible host-guest supramolecular interactions, which explains directly the observed excellent reversibility of this material over 90 adsorption-desorption cycles.
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Apr 2022
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I11-High Resolution Powder Diffraction
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Martin
Schroeder
,
Louis
Kimberley
,
Alena M.
Sheveleva
,
Jiangnan
Li
,
Joseph H.
Carter
,
Xinchen
Kang
,
Gemma L.
Smith
,
Xue
Han
,
Sarah J.
Day
,
Chiu C.
Tang
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Sihai
Yang
Open Access
Abstract: Selective oxidation of benzylic C‐H compounds to ketones is important for the production of a wide range of fine chemicals, and is often achieved using toxic or precious metals catalysts. Here, we report the efficient oxidation of benzylic C‐H groups in a broad range of substrates under mild conditions over a robust metal‐organic framework material, MFM‐170, incorporating redox‐active [Cu2II(O2CR)4] paddlewheel nodes. A comprehensive investigation employing electron paramagnetic resonance (EPR) spectroscopy and synchrotron X‐ray diffraction has identified the critical role of the paddlewheel moiety in activating the oxidant tBuOOH (t‐butyl hydroperoxide) via partial reduction to [CuIICuI(O2CR)4] species.
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Apr 2021
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I19-Small Molecule Single Crystal Diffraction
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William J. F.
Trenholme
,
Daniil I.
Kolokolov
,
Michelle
Bound
,
Stephen P.
Argent
,
Jamie A.
Gould
,
Jiangnan
Li
,
Sarah A.
Barnett
,
Alexander J.
Blake
,
Alexander G.
Stepanov
,
Elena
Besley
,
Timothy L.
Easun
,
Sihai
Yang
,
Martin
Schroeder
Abstract: The desolvated (3,24)-connected metal–organic framework (MOF) material, MFM-160a, [Cu3(L)(H2O)3] [H6L = 1,3,5-triazine-2,4,6-tris(aminophenyl-4-isophthalic acid)], exhibits excellent high-pressure uptake of CO2 (110 wt% at 20 bar, 298 K) and highly selective separation of C2 hydrocarbons from CH4 at 1 bar pressure. Henry’s law selectivities of 79:1 for C2H2:CH4 and 70:1 for C2H4:CH4 at 298 K are observed, consistent with ideal adsorption solution theory (IAST) predictions. Significantly, MFM-160a shows a selectivity of 16:1 for C2H2:CO2. Solid-state 2H NMR spectroscopic studies on partially deuterated MFM-160-d12 confirm an ultra-low barrier (∼2 kJ mol–1) to rotation of the phenyl group in the activated MOF and a rotation rate 5 orders of magnitude slower than usually observed for solid-state materials (1.4 × 106 Hz cf. 1011–1013 Hz). Upon introduction of CO2 or C2H2 into desolvated MFM-160a, this rate of rotation was found to increase with increasing gas pressure, a phenomenon attributed to the weakening of an intramolecular hydrogen bond in the triazine-containing linker upon gas binding. DFT calculations of binding energies and interactions of CO2 and C2H2 around the triazine core are entirely consistent with the 2H NMR spectroscopic observations.
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Feb 2021
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B18-Core EXAFS
B22-Multimode InfraRed imaging And Microspectroscopy
I11-High Resolution Powder Diffraction
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Shaojun
Xu
,
Xue
Han
,
Yujie
Ma
,
Thien D.
Duong
,
Longfei
Lin
,
Emma K.
Gibson
,
Alena
Sheveleva
,
Sarayute
Chansai
,
Alex
Walton
,
Duc-The
Ngo
,
Mark D.
Frogley
,
Chiu C.
Tang
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
C. Richard A.
Catlow
,
Christopher
Hardacre
,
Sihai
Yang
,
Martin
Schroeder
Open Access
Abstract: Efficient catalytic conversion of NO2 to non-harmful species remains an important target for research. State-of-the-art deNOx processes are based upon ammonia (NH3)-assisted selective catalytic reduction (NH3-SCR) over Cu-exchanged zeolites at elevated temperatures. Here, we describe a highly efficient non-thermal plasma (NTP) deNOx process catalyzed by a Cu-embedded metal-organic framework, Cu/MFM-300(Al), at room temperature. Under NTP activation at 25°C, Cu/MFM-300(Al) enables direct decomposition of NO2 into N2, NO, N2O, and O2 without the use of NH3 or other reducing agents. NO2 conversion of 96% with a N2 selectivity of 82% at a turnover frequency of 2.9 h−1 is achieved, comparable to leading NH3-SCR catalysts that use NH3 operating at 250°C–550°C. The mechanism for the rate-determining step (NO→N2) is elucidated by in operando diffuse reflectance infrared Fourier transform spectroscopy, and electron paramagnetic resonance spectroscopy confirms the formation of Cu2+⋯NO nitrosylic adducts on Cu/MFM-300(Al), which facilitates NO dissociation and results in the notable N2 selectivity.
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Feb 2021
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B22-Multimode InfraRed imaging And Microspectroscopy
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Xue
Han
,
Wanpeng
Lu
,
Yinlin
Chen
,
Ivan
Da Silva
,
Jiangnan
Li
,
Longfei
Lin
,
Weiyao
Li
,
Alena M.
Sheveleva
,
Harry G. W.
Godfrey
,
Zhenzhong
Lu
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Yongqiang
Cheng
,
Luke L.
Daemen
,
Laura J.
Mccormick Mcpherson
,
Simon J.
Teat
,
Mark D.
Frogley
,
Svemir
Rudic
,
Pascal
Manuel
,
Anibal J.
Ramirez-Cuesta
,
Sihai
Yang
,
Martin
Schroeder
Diamond Proposal Number(s):
[23782]
Abstract: Ammonia (NH3) is a promising energy resource owing to its high hydrogen density. However, its widespread application is restricted by the lack of efficient and corrosion-resistant storage materials. Here, we report high NH3 adsorption in a series of robust metal–organic framework (MOF) materials, MFM-300(M) (M = Fe, V, Cr, In). MFM-300(M) (M = Fe, VIII, Cr) show fully reversible capacity for >20 cycles, reaching capacities of 16.1, 15.6, and 14.0 mmol g–1, respectively, at 273 K and 1 bar. Under the same conditions, MFM-300(VIV) exhibits the highest uptake among this series of MOFs of 17.3 mmol g–1. In situ neutron powder diffraction, single-crystal X-ray diffraction, and electron paramagnetic resonance spectroscopy confirm that the redox-active V center enables host–guest charge transfer, with VIV being reduced to VIII and NH3 being oxidized to hydrazine (N2H4). A combination of in situ inelastic neutron scattering and DFT modeling has revealed the binding dynamics of adsorbed NH3 within these MOFs to afford a comprehensive insight into the application of MOF materials to the adsorption and conversion of NH3.
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Feb 2021
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