E01-JEM ARM 200CF
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Naomi
Lawes
,
Igor
Kowalec
,
Sofia
Mediavilla-Madrigal
,
Kieran J.
Aggett
,
Louise R.
Smith
,
Malcolm
Dearg
,
Thomas J. A.
Slater
,
Eimear
Mccarthy
,
Herzain I.
Rivera-Arrieta
,
Matthias
Scheffler
,
David J.
Morgan
,
David J.
Willock
,
Andrew M.
Beale
,
Andrew J.
Logsdail
,
Nicholas F.
Dummer
,
Michael
Bowker
,
C. Richard A.
Catlow
,
Stuart H.
Taylor
,
Graham J.
Hutchings
Diamond Proposal Number(s):
[3104]
Open Access
Abstract: A series of PdZn/TiO2 catalysts prepared by chemical vapor impregnation (CVI) were tested for CO2 hydrogenation at 20 bar pressure and at temperatures of 230–270 °C. Changing the Pd and Zn molar ratio (Zn:Pd = 0–20) in a PdZn/TiO2 catalyst has a dramatic effect on selectivity for the CO2 hydrogenation reaction. Pd alone shows three main products: methanol, CO, and methane. Addition of small quantities of Zn results in the formation of a PdZn alloy, preventing methanation. At equimolar ratios of Pd and Zn, a 1:1 β-PdZn alloy is formed and a reverse water gas shift catalyst is produced. Adding Zn in excess relative to the Pd loading results in the formation of ZnO on the TiO2 surface in addition to the PdZn alloy, dramatically increasing methanol selectivity from 5% at Zn:Pd = 1 to 55% for Zn:Pd = 2. Through a combination of theory and experiment, the active site for methanol synthesis is concluded to be the interface between PdZn nanoparticles and the ZnO overlayer on the TiO2, where interfacial formate can react with hydrogen dissociated by the metal nanoparticle.
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Jan 2026
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B07-B1-Versatile Soft X-ray beamline: High Throughput ES1
B18-Core EXAFS
I14-Hard X-ray Nanoprobe
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Lotfi
Boudjema
,
Anil Kumar
Dahiya
,
Ivan
Da Silva
,
Diego
Gianolio
,
Izuchika
Nduka
,
Manfred Erwin
Schuster
,
Gea T.
Van De Kerkhof
,
Paulina
Kalinowska
,
Emilio
Borrego-Marin
,
Jorge A. R.
Navarro
,
Valentina
Colombo
,
June
Mccorquodale
,
David C.
Grinter
,
Pilar
Ferrer
,
Georg
Held
,
C. Richard A.
Catlow
,
Rosa
Arrigo
Diamond Proposal Number(s):
[28630]
Open Access
Abstract: We investigate the rapid microwave-assisted solvothermal synthesis of a Cu-MOF (Metal-Organic Framework) with open metal sites, with a focus on understanding its CO2 capture properties in relation to phase purity and stability. A combined experimental and theoretical approach is used to identify the MOF structural features involved in the adsorption process. Specifically, Cu(I) defects are found playing an important role in the CO2 adsorption process, with the Cu-1 sample, synthesized using an optimized ligand/Cu precursor ratio for highest phase purity, exhibiting more abundant Cu(I) defects as well as highest adsorption capacity. Grand Canonical Monte Carlo simulations show that the Cu(I) sites exhibit a greater affinity for CO2 adsorption compared to the Cu(II) sites. In situ spectroscopic soft and hard X-ray absorption fine structure spectroscopy confirm the conversion of Cu(I) to Cu(II) upon CO2 chemisorption, with this conversion being more pronounced in the core of the particles. The simulations are used to estimate the fraction of Cu(I) defects and Cu(II) sites present within the Cu-1 MOF and to validate the experimental isotherm. Overall, this study provides insights into the CO2 capture properties of GIF-KUC Cu-MOFs and highlights the importance of phase purity for achieving high adsorption performance.
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Jun 2025
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Open Access
Abstract: Publishing supporting data significantly impacts researchers' productivity, especially in experiments requiring extensive tracking of data, processing steps, parameters, and outputs. A managed workflow environment, combined with RO-Crates, addresses these data management challenges. Workflows provide an alternative for handling complex data analyses by orchestrating various processing tools. The RO-Crate format, a community-driven proposal for packaging data, provenance, and workflows, facilitates publishing and reproducibility. The Galaxy workflow management system integrates workflows and RO-Crates, enabling the export of analyses, which can be shared and restored by other users. Using Galaxy, we demonstrate how to improve support for reproducibility. We tested our approach by designing an experiment using diverse supporting data from selected papers. In the experiment, we identified specific FAIRness and completeness issues hindering result reproduction, even when authors made significant efforts to document and publish their supporting data. In comparison, the proposed approach supports reproducibility by packaging datasets in RO-Crate format, streamlining the process. The Galaxy RO-Crates, published as supporting materials, enhance data sharing, transparency, and reproducibility, thus supporting the advancement of FAIR research practices in catalysis research.
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Mar 2025
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I11-High Resolution Powder Diffraction
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Xinchen
Kang
,
Lili
Li
,
Hengan
Wang
,
Tian
Luo
,
Shaojun
Xu
,
Yinlin
Chen
,
Joseph H.
Carter
,
Zi
Wang
,
Alena M.
Sheveleva
,
Kai
Lyu
,
Xue
Han
,
Floriana
Tuna
,
Eric J. L.
Mcinnes
,
Chiu C.
Tang
,
Lifei
Liu
,
Buxing
Han
,
Emma K.
Gibson
,
C. Richard A.
Catlow
,
Sihai
Yang
,
Martin
Schroeder
Diamond Proposal Number(s):
[33115]
Open Access
Abstract: Catalytic cleavage of β-O-4 linkages is an essential but challenging step in the depolymerisation of lignin. Here, we report the templated electrosynthesis of a hydrophobic metal-organic polyhedral catalyst (Cu-MOP-e), which exhibits excellent hydrothermal stability and exceptional activity for this reaction. The oxidative cleavage of 2-phenoxyacetophenone, 1, a lignin model compound, over Cu-MOP-e at 90 oC for 1 h affords full conversion with yields of the monomer products phenol and benzoic acid of 99%. The reusability of Cu-MOP-e has been confirmed by carrying out ten cycles of reaction. The mechanism of catalyst-substrate binding has been investigated by high resolution synchrotron X-ray powder diffraction, in situ X-ray absorption spectroscopy, electron paramagnetic resonance spectroscopy and density functional theory calculations. The combination of optimal porosity and active Cu(II) sites provides confined binding of 2-phenoxyacetophenone, thus promoting the cleavage of β-O-4 linkage under relatively mild conditions.
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Dec 2024
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B18-Core EXAFS
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Santhosh K.
Matam
,
Preetam K.
Sharma
,
Eileen H.
Yu
,
Charalampos
Drivas
,
Mohammad D.
Khan
,
Martin
Wilding
,
Nitya
Ramanan
,
Diego
Gianolio
,
Mark A.
Isaacs
,
Shaoliang
Guan
,
Philip R.
Davies
,
C. Richard A.
Catlow
Diamond Proposal Number(s):
[29271]
Open Access
Abstract: We present a novel operando X-ray absorption spectroscopic (XAS) flow cell, consisting of a gas chamber for CO2 and a liquid chamber for the electrolyte, to monitor electrochemical CO2 reduction (eCO2R) over a gas diffusion electrode (GDE). The feasibility of the flow cell is demonstrated by collecting XAS data (during eCO2R over Cu-GDE) in a transmission mode at the Cu K-edge. The dynamic behaviour of copper during eCO2R is captured by XAS which is complemented by quasi in situ Raman and X-ray photoelectron spectroscopy (XPS). The linear combination analyses (LCA) of X-ray absorption near edge structure (XANES) indicate that copper oxides are the only species present during the first 20 min of eCO2R, corroborated by complementary Raman and XPS. Significantly, the complementary spectroscopic data suggests that the copper composition in the bulk and on the surface Cu-GDE evolve differently at and above 30 min of eCO2R. LCA indicates that at 60 min, 77% of copper occurs as metallic Cu and the remainder 23% in Cu (II) oxidation state, which is not evident from XPS that shows 100% of copper in < 2+ oxidation state. Thus, the Cu (II) is probably in the bulk of Cu-GDE, as also evident from Raman. The ethylene formation correlates very well with the occurrence of copper oxides and hydroxide species in Cu-GDE. The results not only demonstrate the applicability and versatility of the operando XAS GDE flow cell, but also illustrate the unique advantages of combining XAS with complementary Raman and XPS that enables the monitoring of the catalyst structural evolution from the bulk to surface and surface adsorbed species.
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Dec 2024
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I20-EDE-Energy Dispersive EXAFS (EDE)
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Donato
Decarolis
,
Monik
Panchal
,
Matthew
Quesne
,
Khaled
Mohammed
,
Shaojun
Xu
,
Mark
Isaacs
,
Adam H.
Clark
,
Luke L.
Keenan
,
Takuo
Wakisaka
,
Kohei
Kusada
,
Hiroshi
Kitagawa
,
C. Richard A.
Catlow
,
Emma K.
Gibson
,
Alexandre
Goguet
,
Peter
Wells
Diamond Proposal Number(s):
[21593]
Open Access
Abstract: Unravelling kinetic oscillations, which arise spontaneously during catalysis, has been a challenge for decades but is important not only to understand these complex phenomena but also to achieve increased activity. Here we show, through temporally and spatially resolved operando analysis, that CO oxidation over Rh/Al2O3 involves a series of thermal levering events—CO oxidation, Boudouard reaction and carbon combustion—that drive oscillatory CO2 formation. This catalytic sequence relies on harnessing localized temperature episodes at the nanoparticle level as an efficient means to drive reactions in situations in which the macroscopic conditions are unfavourable for catalysis. This insight provides a new basis for coupling thermal events at the nanoscale for efficient harvesting of energy and enhanced catalyst technologies.
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Jul 2024
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B18-Core EXAFS
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Diego
Gianolio
,
Michael D.
Higham
,
Matthew G.
Quesne
,
Matteo
Aramini
,
Ruoyu
Xu
,
Alex I.
Large
,
Georg
Held
,
Juan-Jesús
Velasco-Vélez
,
Michael
Haevecker
,
Axel
Knop-Gericke
,
Chiara
Genovese
,
Claudio
Ampelli
,
Manfred Erwin
Schuster
,
Siglinda
Perathoner
,
Gabriele
Centi
,
C. Richard A.
Catlow
,
Rosa
Arrigo
Diamond Proposal Number(s):
[24919]
Open Access
Abstract: Operando soft and hard X-ray spectroscopic techniques were used in combination with plane-wave density functional theory (DFT) simulations to rationalize the enhanced activities of Zn-containing Cu nanostructured electrocatalysts in the electrocatalytic CO2 hydrogenation reaction. We show that at a potential for CO2 hydrogenation, Zn is alloyed with Cu in the bulk of the nanoparticles with no metallic Zn segregated; at the interface, low reducible Cu(I)–O species are consumed. Additional spectroscopic features are observed, which are identified as various surface Cu(I) ligated species; these respond to the potential, revealing characteristic interfacial dynamics. Similar behavior was observed for the Fe–Cu system in its active state, confirming the general validity of this mechanism; however, the performance of this system deteriorates after successive applied cathodic potentials, as the hydrogen evolution reaction then becomes the main reaction pathway. In contrast to an active system, Cu(I)–O is now consumed at cathodic potentials and not reversibly reformed when the voltage is allowed to equilibrate at the open-circuit voltage; rather, only the oxidation to Cu(II) is observed. We show that the Cu–Zn system represents the optimal active ensembles with stabilized Cu(I)–O; DFT simulations rationalize this observation by indicating that Cu–Zn–O neighboring atoms are able to activate CO2, whereas Cu–Cu sites provide the supply of H atoms for the hydrogenation reaction. Our results demonstrate an electronic effect exerted by the heterometal, which depends on its intimate distribution within the Cu phase and confirms the general validity of these mechanistic insights for future electrocatalyst design strategies.
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Apr 2023
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B22-Multimode InfraRed imaging And Microspectroscopy
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Mar 2023
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E01-JEM ARM 200CF
E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[31082]
Open Access
Abstract: Despite extensive efforts to develop high-performance H2 evolution catalysts, this remains a major challenge. Here, we demonstrate the use of Cd/Pt precursor solutions for significant photocatalytic H2 production (154.7 mmol g-1 h-1), removing the need for a pre-synthesized photocatalyst. In addition, we also report simultaneous in-situ synthesis of Pt single-atoms anchored CdS nanoparticles (PtSA-CdSIS) during photoirradiation. The highly dispersed in-situ incorporation of extensive Pt single atoms on CdSIS enables the enhancement of active sites and suppresses charge recombination, which results in exceptionally high solar-to-hydrogen conversion efficiency of ~1% and an apparent quantum yield of over 91% (365 nm) for H2 production. Our work not only provides a promising strategy for maximising H2 production efficiency but also provides a green process for H2 production and the synthesis of highly photoactive PtSA-CdSIS nanoparticles.
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Feb 2023
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B18-Core EXAFS
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Man
Zhang
,
Shaojun
Xu
,
Mebrouka
Boubeche
,
Donato
Decarolis
,
Yizhe
Huang
,
Biying
Liu
,
Emma K.
Gibson
,
Xin
Li
,
Yuchen
Wang
,
Huixia
Luo
,
C. Richard A.
Catlow
,
Kai
Yan
Diamond Proposal Number(s):
[19850]
Abstract: Green and highly selective synthesis of organonitrogen chemicals (ONCs) using the renewable energy source biomass over noble-metal free solid catalysts under common room temperature and pressure conditions is still a major challenge. Here, we report a sustainable electrochemical method for selective synthesis of several valuable ONCs with high yields using biomass-derived furanic aldehydes over greenly fabricated TiS2 nanosheets through a facile synthesis. Based on a range of characterization techniques including high-resolution transmission electron microscopy and X-ray absorption fine structure, a well-defined structure of the TiS2 nanosheets (3.86 nm with 1T phase) was constructed. These as-prepared catalysts were applied to the electrochemical reductive amination (ERA) of three biomass-derived aldehydes, i.e. furfural (FF), 5-methylfurfural (MF) and 5-hydroxymethylfurfural (HMF), and exhibited superior performance whereby over 95% conversion of each furanic aldehyde and nearly perfect selectivity of ONCs were achieved. TiS2 nanosheets, in particular, exhibited a marked ∼2-fold increase in conversion (∼49%) compared with the monometallic Ti electrode. Besides, the reaction kinetics and rational pathway were also studied. In addition, these exfoliated TiS2 nanosheets maintained high durability over 6 h, providing a promising and versatile route for the sustainable upgrading of biomass-derived sources.
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Nov 2022
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