B22-Multimode InfraRed imaging And Microspectroscopy
|
Thien D.
Duong
,
Sergey A.
Sapchenko
,
Ivan
Da Silva
,
Harry G. W.
Godfrey
,
Yongqiang
Cheng
,
Luke L.
Daemen
,
Pascal
Manuel
,
Mark D.
Frogley
,
Gianfelice
Cinque
,
Anibal J.
Ramirez-cuesta
,
Sihai
Yang
,
Martin
Schroeder
Diamond Proposal Number(s):
[14938]
Open Access
Abstract: Metal–organic frameworks (MOFs) functionalised with amine, amide and hydroxyl groups show great promise for CO2 binding due to their ability to form hydrogen bonds to CO2. Herein we report the adsorption and selectivity of CO2 in four iso-reticular MOFs adopting the NbO topology. Functionalisation of the parent MOF, MFM-102, with –NO2, –NH2 and alkyl groups leads to an enhancement of CO2 adsorption of up to 36% for the NO2-decorated MOF and with raised selectivity. MFM-102-NO2 shows the highest adsorption capacity for CO2 (184 cm3 g−1 at 273 K and 1.0 bar) within this series, comparable to the best-behaving iso-reticular MOFs. At 298 K and 1.0 bar, MFM-102-NO2 shows a CO2/CH4 selectivity of 5.0. In situ inelastic neutron scattering and synchrotron FT-IR micro-spectroscopy were employed to elucidate the host–guest interaction dynamics within CO2-loaded MFM-102-NO2. Neutron powder diffraction enabled the direct observation of the preferred binding domains in MFM-102-NO2, and, to the best of our knowledge, we report the first example of CO2 binding to a –NO2 group in a porous MOF. Synergistic effects between the –NO2 group and the open metal sites lead to optimal binding of CO2 molecules within MFM-102-NO2 via hydrogen bonding to C–H groups.
|
May 2020
|
|
I11-High Resolution Powder Diffraction
|
Diamond Proposal Number(s):
[22138]
Abstract: Coordination pillared-layer metal-organic frameworks (CPL-MOFs), such as CPL-2, are interesting versatile and porous materials with the potential for gas adsorption and separation. CPL-2 shows the unusual and gradual linker rotation upon the adsorption of ethylene (C2H4) and ethane (C2H6), leading to a fully reversible adsorption isotherm specifically under the conditions studied. Grand canonical Monte Carlo (GCMC) simulations showed that it is impossible to accommodate the experimentally observed loadings of C2H4 and C2H6 in CPL-2 using the crystallographic structure reported in the literature. According to the simulation findings, the pore expansion might be initiated by the clockwise 4,4′-bipyridine (bpy) pillar linker rotation. The pillar rotation leads to the enlarged pore volume, rendering additional adsorption sites, which are not present in the pristine structure. In situ synchrotron PXRD experiments for C2H4 and C2H6 adsorption on CPL-2 confirmed the occurrence of pore expansion in CPL-2 MOF. The combined experimental and simulation study shows for the first time that the linker rotation in CPL-2 can result in a adsorption isotherm without hysteresis. This work developed a real insight into the nature of pillared-layer MOFs, and the revealed structural changes could be potentially exploited to enhance alkene and alkane working capacities of such microporous materials.
|
Feb 2020
|
|
B18-Core EXAFS
I11-High Resolution Powder Diffraction
|
Longfei
Lin
,
Alena M.
Sheveleva
,
Ivan
Da Silva
,
Christopher M. A.
Parlett
,
Zhimou
Tang
,
Yueming
Liu
,
Mengtian
Fan
,
Xue
Han
,
Joseph H.
Carter
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Yongqiang
Cheng
,
Luke L.
Daemen
,
Svemir
Rudic
,
Anibal J.
Ramirez-cuesta
,
Chiu C.
Tang
,
Sihai
Yang
Diamond Proposal Number(s):
[15151, 24726]
Abstract: The efficient production of light olefins from renewable biomass is a vital and challenging target to achieve future sustainable chemical processes. Here we report a hetero-atomic MFI-type zeolite (NbAlS-1), over which aqueous solutions of γ-valerolactone (GVL), obtained from biomass-derived carbohydrates, can be quantitatively converted into butenes with a yield of >99% at ambient pressure under continuous flow conditions. NbAlS-1 incorporates simultaneously niobium(v) and aluminium(iii) centres into the framework and thus has a desirable distribution of Lewis and Brønsted acid sites with optimal strength. Synchrotron X-ray diffraction and absorption spectroscopy show that there is cooperativity between Nb(v) and the Brønsted acid sites on the confined adsorption of GVL, whereas the catalytic mechanism for the conversion of the confined GVL into butenes is revealed by in situ inelastic neutron scattering, coupled with modelling. This study offers a prospect for the sustainable production of butene as a platform chemical for the manufacture of renewable materials.
|
Dec 2019
|
|
B23-Circular Dichroism
I19-Small Molecule Single Crystal Diffraction
|
Zongsu
Han
,
Kunyu
Wang
,
Yifan
Guo
,
Wenjie
Chen
,
Jiale
Zhang
,
Xinran
Zhang
,
Giuliano
Siligardi
,
Sihai
Yang
,
Zhen
Zhou
,
Pingchuan
Sun
,
Wei
Shi
,
Peng
Cheng
Diamond Proposal Number(s):
[20293]
Open Access
Abstract: The integration of luminescence and chirality in easy-scalable metal-organic frameworks gives rise to the development of advanced luminescent sensors. To date, the synthesis of chiral metal-organic frameworks is poorly predictable and their chirality primarily originates from components that constitute the frameworks. By contrast, the introduction of chirality into the pores of metal-organic frameworks has not been explored to the best of our knowledge. Here, we demonstrate that chirality can be introduced into an anionic Zn-based metal-organic framework via simple cation exchange, yielding dual luminescent centers comprised of the ligand and Tb3+ ions, accompanied by a chiral center in the pores. This bifunctional material shows enantioselectivity luminescent sensing for a mixture of stereoisomers, demonstrated for Cinchonine and Cinchonidine epimers and amino alcohol enantiomers, from which the quantitative determination of the stereoisomeric excess has been obtained. This study paves a pathway for the design of multifunctional metal-organic framework systems as a useful method for rapid sensing of chiral molecules.
|
Nov 2019
|
|
B22-Multimode InfraRed imaging And Microspectroscopy
I11-High Resolution Powder Diffraction
I12-JEEP: Joint Engineering, Environmental and Processing
|
Harry G. W.
Godfrey
,
Lydia
Briggs
,
Xue
Han
,
William J. F.
Trenholme
,
Christopher
Morris
,
Mathew
Savage
,
Louis
Kimberley
,
Oxana
Magdysyuk
,
Michael
Drakopoulos
,
Claire A.
Murray
,
Chiu C.
Tang
,
Mark D.
Frogley
,
Gianfelice
Cinque
,
Sihai
Yang
,
Martin
Schroeder
Diamond Proposal Number(s):
[11278]
Open Access
Abstract: Understanding the mechanism of assembly and function of metal-organic frameworks (MOFs) is important for the development of practical materials. Herein, we report a time-resolved diffraction analysis of the kinetics of formation of a robust MOF, MFM-300(Fe), which shows high adsorption capacity for CO2 (9.55 mmol g−1 at 293 K and 20 bar). Applying the Avrami-Erofe’ev and the two-step kinetic Finke-Watzky models to in situ high-energy synchrotron X-ray powder diffraction data obtained during the synthesis of MFM-300(Fe) enables determination of the overall activation energy of formation (50.9 kJ mol−1), the average energy of nucleation (56.7 kJ mol−1), and the average energy of autocatalytic growth (50.7 kJ mol−1). The synthesis of MFM-300(Fe) has been scaled up 1000-fold, enabling the successful breakthrough separations of the CO2/N2 mixture in a packed-bed with a selectivity for CO2/N2 of 21.6. This study gives an overall understanding for the intrinsic behaviors of this MOF system, and we have determined directly the binding domains and dynamics for adsorbed CO2 molecules within the pores of MFM-300(Fe).
|
Nov 2019
|
|
B22-Multimode InfraRed imaging And Microspectroscopy
|
Gemma L.
Smith
,
Jennifer E.
Eyley
,
Xue
Han
,
Xinran
Zhang
,
Jiangnan
Li
,
Nicholas M.
Jacques
,
Harry G. W.
Godfrey
,
Stephen P.
Argent
,
Laura J.
Mccormick Mcpherson
,
Simon J.
Teat
,
Yongqiang
Cheng
,
Mark D.
Frogley
,
Gianfelice
Cinque
,
Sarah
Day
,
Chiu C.
Tang
,
Timothy L.
Easun
,
Svemir
Rudic
,
Anibal J.
Ramirez-cuesta
,
Sihai
Yang
,
Martin
Schroeder
Abstract: Emissions of SO2 from flue gas and marine transport have detrimental impacts on the environment and human health, but SO2 is also an important industrial feedstock if it can be recovered, stored and transported efficiently. Here we report the exceptional adsorption and separation of SO2 in a porous material, [Cu2(L)] (H4L = 4′,4‴-(pyridine-3,5-diyl)bis([1,1′-biphenyl]-3,5-dicarboxylic acid)), MFM-170. MFM-170 exhibits fully reversible SO2 uptake of 17.5 mmol g−1 at 298 K and 1.0 bar, and the SO2 binding domains for trapped molecules within MFM-170 have been determined. We report the reversible coordination of SO2 to open Cu(ii) sites, which contributes to excellent adsorption thermodynamics and selectivities for SO2 binding and facile regeneration of MFM-170 after desorption. MFM-170 is stable to water, acid and base and shows great promise for the dynamic separation of SO2 from simulated flue gas mixtures, as confirmed by breakthrough experiments.
|
Oct 2019
|
|
B22-Multimode InfraRed imaging And Microspectroscopy
|
Xinchen
Kang
,
Kai
Lyu
,
Lili
Li
,
Jiangnan
Li
,
Louis
Kimberley
,
Bin
Wang
,
Lifei
Liu
,
Yongqiang
Cheng
,
Mark D.
Frogley
,
Svemir
Rudic
,
Anibal J.
Ramirez-cuesta
,
Robert A. W.
Dryfe
,
Buxing
Han
,
Sihai
Yang
,
Martin
Schroder
Diamond Proposal Number(s):
[19171]
Open Access
Abstract: Incorporation of mesopores and active sites into metal-organic framework (MOF) materials to uncover new efficient catalysts is a highly desirable but challenging task. We report the first example of a mesoporous MOF obtained by templated electrosynthesis using an ionic liquid as both electrolyte and template. The mesoporous Cu(II)-MOF MFM-100 has been synthesised in 100 seconds at room temperature, and this material incorporates crystal defects with uncoupled Cu(II) centres as evidenced by confocal fluorescence microscopy and electron paramagnetic resonance spectroscopy. MFM-100 prepared in this way shows exceptional catalytic activity for the aerobic oxidation of alcohols to produce aldehydes in near quantitative yield and selectivity under mild conditions, as well as having excellent stability and reusability over repeated cycles. The catalyst-substrate binding interactions have been probed by inelastic neutron scattering. This study offers a simple strategy to create mesopores and active sites simultaneously via electrochemical formation of crystal defects to promote efficient catalysis using MOFs.
|
Oct 2019
|
|
I11-High Resolution Powder Diffraction
|
Xinran
Zhang
,
Ivan
Da Silva
,
Rodrigo
Fazzi
,
Alena M.
Sheveleva
,
Xue
Han
,
Ben F.
Spencer
,
Sergey A.
Sapchenko
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Ming
Li
,
Sihai
Yang
,
Martin
Schroder
Diamond Proposal Number(s):
[21079]
Abstract: We report a comparative study of the binding of I2 (iodine) in a pair of redox-active metal–organic framework (MOF) materials, MFM-300(VIII) and its oxidized, deprotonated analogue, MFM-300(VIV). Adsorption of I2 in MFM-300(VIII) triggers a host-to-guest charge-transfer, accompanied by a partial (∼30%) oxidation of the VIII centers in the host framework and formation of I3– species residing in the MOF channels. Importantly, this charge-transfer induces a significant enhancement in the electrical conductivity (Δσ = 700000) of I2@MFM-300(VIII/IV) in comparison to MFM-300(VIII). In contrast, no host–guest charge-transfer or apparent change in the conductivity was observed upon adsorption of I2 in MFM-300(VIV). High-resolution synchrotron X-ray diffraction of I2@MFM-300(VIII/IV) confirms the first example of self-aggregation of adsorbed iodine species (I2 and I3–) into infinite helical chains within a MOF.
|
Sep 2019
|
|
I19-Small Molecule Single Crystal Diffraction
|
Peter
Rought
,
Christopher
Marsh
,
Simona
Pili
,
Ian P.
Silverwood
,
Victoria
Garcia Sakai
,
Ming
Li
,
Martyn
Brown
,
Stephen P.
Argent
,
Inigo
Vitorica-yrezabal
,
George
Whitehead
,
Mark R.
Warren
,
Sihai
Yang
,
Martin
Schroeder
Diamond Proposal Number(s):
[13650, 12517]
Open Access
Abstract: Three multi-carboxylic acid functionalised ligands have been designed, synthesised and utilised to synthesise the new barium-based MOFs, MFM-510, -511, and -512, which show excellent stability to water-vapour. MFM-510 and MFM-511 show moderate proton conductivities (2.1 x10-5 and 5.1 x10-5 S cm-1, respectively) at 99RH% and 298 K, attributed to the lack of free protons or hindered proton diffusion within the framework structures. In contrast, MFM-512, which incorporates a pendant carboxylic acid group directed into the pore of the framework, shows a two orders of magnitude enhancement in proton conductivity (2.9 x10-3 S cm-1). Quasi-elastic neutron scattering (QENS) suggests that the proton dynamics of MFM-512 are mediated by “free diffusion inside a sphere” confirming that incorporation of free carboxylic acid groups within the pores of MOFs is an efficient albeit a synthetically challenging strategy to improve proton conductivity.
|
Nov 2018
|
|
I11-High Resolution Powder Diffraction
|
Diamond Proposal Number(s):
[14341]
Abstract: We report a record-high SO2 adsorption capacity of 12.3 mmol g–1 in a robust porous material, MFM-601, at 298 K and 1.0 bar. SO2 adsorption in MFM-601 is fully reversible and highly selective over CO2 and N2. The binding domains for adsorbed SO2 and CO2 molecules in MFM-601 have been determined by in situ synchrotron X-ray diffraction experiments, giving insights at the molecular level to the basis of the observed high selectivity.
|
Nov 2018
|
|
