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Instruments / Technical Area	Publication Details	Published
B07-B1-Versatile Soft X-ray beamline: High Throughput ES1 B18-Core EXAFS E01-JEM ARM 200CF E02-JEM ARM 300CF	Highly stable manganese oxide cathode material enabled by Grotthuss topochemistry for aqueous zinc ion batteries Fangjia Zhao , Jianwei Li , Arunabhiram Chutia , Longxiang Liu , Liqun Kang , Feili Lai , Haobo Dong , Xuan Gao , Yeshu Tan , Tianxi Liu , Ivan P. Parkin , Guanjie He Energy & Environmental Science 22 DOI: 10.1039/D3EE04161A Diamond Proposal Number(s): [32905, 29340, 32058] Open Access Show Abstract ▼ Abstract: The design and synthesis of manganese oxide-based materials with high-rate performance and long cycle life is a major challenge for aqueous zinc-ion batteries (AZIBs). This research reports the presence of a synergistic collaboration between vacancies, lattice water and nickel ions on enhancing the hydrated protons hopping via the Grotthuss mechanism for high-performance zinc ion batteries. The Grotthuss mechanism allows for the efficient transfer of a proton charge without the actual movement of the molecule over long distances, resulting in high ionic conductivity. NiMn3O7·3H2O achieves a capacity of 318 mA h g−1 under 200 mA g−1 and 121 mA h g−1 under 5 A g−1 with a retention of 91% after 4000 cycles. The relationship between the remarkable performance and Grotthuss topochemistry is investigated using techniques including synchrotron X-ray absorption spectroscopy and density functional theory. Protons prefer to bond with O2− ions on the Mn–O layer, and proton transfer is favoured in the presence of vacancies. The continuous hopping of protons within the host material induces periodic, temporary local structural changes in the lattice. This dynamic behaviour alters the energy barriers for ions intercalation and deintercalation. Nickel ions facilitate the ongoing mobility of hydrated protons via Grotthuss hopping by preserving the system's electrical neutrality, which counterbalances the dynamic changes caused by proton migration. This study provides insight into the Grotthuss conduction mechanism for the development of high-performance cathode materials in AZIBs.	Jan 2024
B07-B1-Versatile Soft X-ray beamline: High Throughput ES1 E02-JEM ARM 300CF	Spectroscopic identification of active sites of oxygen-doped carbon for selective oxygen reduction to hydrogen peroxide Longxiang Liu , Liqun Kang , Arunabhiram Chutia , Jianrui Feng , Martyna Michalska , Pilar Ferrer , David Grinter , Georg Held , Yeshu Tan , Fangjia Zhao , Fei Guo , David Hopkinson , Christopher Allen , Yanbei Hou , Junwen Gu , Ioannis Papakonstantinou , Paul Shearing , Dan Brett , Ivan P. Parkin , Guanjie He Angewandte Chemie International Edition DOI: 10.1002/anie.202303525 Diamond Proposal Number(s): [29340, 32501, 30614, 29809, 32058] Open Access Show Abstract ▼ Abstract: The electrochemical synthesis of hydrogen peroxide (H2O2) via a two-electron (2e-) oxygen reduction reaction (ORR) process provides a promising alternative to replace the energy-intensive anthraquinone process. However, the development of efficient electrocatalysts is still facing lots of challenges like insufficient understanding of active sites. Herein, we develop a facile template-protected strategy to synthesize a highly active quinone-rich porous carbon catalyst (PCC) for H2O2 electrochemical production. The optimized PCC900 exhibits unprecedented activity and selectivity, of which the onset potential reaches 0.83 V vs. reversible hydrogen electrode in 0.1 M KOH and the H2O2 selectivity is over 95 % in a wide potential range. Comprehensive synchrotron-based near-edge X-ray absorption fine structure (NEXAFS) spectroscopy combined with electrocatalytic characterizations reveals the positive correlation between quinone content and 2e- ORR performance. The effectiveness of chair-form quinone groups as the most efficient active sites is highlighted by the molecule-mimic strategy and theoretical analysis.	Mar 2023
B18-Core EXAFS	Dual-site mediated hydrogenation catalysis on Pd/NiO: selective biomass transformation and maintaining catalytic activity at low Pd loading Sebastiano Campisi , Carine E. Chan-Thaw , Lidia E. Chinchilla , Arunabhiram Chutia , Gianluigi A. Botton , Khaled M. H. Mohammed , Nikolaos Dimitratos , Peter Wells , Alberto Villa Acs Catalysis DOI: 10.1021/acscatal.0c00414 Diamond Proposal Number(s): [10306] Open Access Show Abstract ▼ Abstract: Creating a new chemical ecosystem based on platform chemicals derived from waste biomass has significant challenges; catalysts need to be able to convert these highly functionalised molecules to specific target chemicals, economical – not relying on large quantities of precious metals - and maintain activity over many cycles. Herein, we demonstrate how Pd/NiO is able to direct the selectivity of furfural hydrogenation and maintain performance at low Pd loading by a unique dual-site mechanism. Sol-immobilization was used to prepare 1 wt% Pd nanoparticles supported on NiO and TiO2, with the Pd/NiO catalyst showing enhanced activity with a significantly different selectivity profile; Pd/NiO favours tetrahydrofurfuryl alcohol (72%), whereas Pd/TiO2 produces furfuryl alcohol as the major product (68%). Density functional theory studies evidenced significant differences on the adsorption of furfural on both NiO and Pd surfaces. Based on this observation we hypothesised that the role of Pd was to dissociate hydrogen, with the NiO surface adsorbing furfural. This dual-site hydrogenation mechanism was supported by comparing the performance of 0.1 wt% Pd/NiO and 0.1 wt% Pd/TiO2. In this study, the 0.1 and 1 wt% Pd/NiO catalysts had a comparable activity, whereas there was a 10 fold reduction in performance for 0.1 wt.% Pd/TiO2. When using TiO2 as the support the Pd nanoparticles are responsible for both hydrogen dissociation and furfural adsorption, and the activity is strongly correlated with the effective metal surface area. This work has significant implications for the upgrading of bio-derived feedstocks, suggesting alternative ways for promoting selective transformations and reducing the reliance on precious metals.	Apr 2020
B18-Core EXAFS	Carbidisation of Pd nanoparticles by ethene decomposition, with methane production Michael Bowker , Wilm Jones , Peter P. Wells , Emma K. Gibson , Arunabhiram Chutia , Ian P. Silverwood , C. Richard A. Catlow Chemcatchem DOI: 10.1002/cctc.201900795 Open Access Show Abstract ▼ Abstract: In the presence of oxygenated organic molecules pure Pd, which is widely used in chemicals processing and the pharmaceutical industry, tends to defunctionalise and dehydrogenate such molecules to H2, CO and surface/bulk carbon, in the form of a palladium carbide. We have investigated the formation of this carbide by ethene adsorption using a variety of techniques, including pulsed flow reaction measurements, XAS and DFT calculations of the lattice expansion during carbidisation. These experiments show that two main reactions take place above 500K, that is, both total dehydrogenation, but also disproportionation to methane and the carbide, after which the activity of the Pd is completely lost. We estimate the value of x in PdCx to be 0.28 (±0.03), and show by computer modelling that this fits the lattice expansion observed by XAFS, and that there is charge transfer to C from Pd of around 0.2‐0.4 e.	Jun 2019
B18-Core EXAFS	Directed aqueous-phase reforming of glycerol through tailored platinum nanoparticles J. Callison , N. D. Subramanian , S. M. Rogers , A. Chutia , D. Gianolio , C. R. A. Catlow , P. P. Wells , N. Dimitratos Applied Catalysis B: Environmental 238, 618 - 628 DOI: 10.1016/j.apcatb.2018.07.008 Diamond Proposal Number(s): [10306] Open Access Show Abstract ▼ Abstract: Sustainable technologies require both renewable feedstocks and catalysts that are able to direct their conversion to specific products. We establish a structure-activity relationship for the aqueous phase reforming of glycerol over 2% Pt/Al2O3 catalysts, whereby the reaction pathway can be controlled to produce either hydrogen or 1,2-propanediol as the main product. Using the colloidal synthesis method, the reduction temperature was altered to produce Pt nanoparticle catalysts supported on Al2O3 with varying Pt particle size. The catalytic activity of the samples for the APR of glycerol resulted in a higher conversion of glycerol (34%) for the larger Pt particle size of ∼3.5 nm, producing the liquid 1,2-propanediol as the major product with a yield of 12.5%, whereas smaller particles of ∼2.2 nm gave hydrogen as the main product (5.5% yield). This work demonstrates how the APR of glycerol can be tuned to yield both valuable liquid and gas products using tailored Pt nanoparticles.	Dec 2018
B18-Core EXAFS	The adsorption of Cu on the CeO2(110) surface Arunabhiram Chutia , Emma Gibson , Matthew R. Farrow , Peter Wells , David O. Scanlon , Nikolaos Dimitratos , David J. Willock , C. Richard A. Catlow Physical Chemistry Chemical Physics DOI: 10.1039/C7CP04144F Diamond Proposal Number(s): [10306, 15151] Open Access Show Abstract ▼ Abstract: We report a detailed density functional theory (DFT) study in conjunction with X-ray absorption fine structure (XAFS) experiments on the geometrical and local electronic properties of Cu adatoms and Cu(II) ions in presence of water molecules and of CuO nanoclusters on the CeO2(110) surface. Our study of (CuO)n(=1, 2 & 4) clusters on CeO2(110) shows that based on the Cu–O environment, the geometrical properties of these clusters may vary and their presence may lead to relatively higher localization of charges on the exposed surfaces. We find that in presence of an optimum concentration of water molecules, Cu has a square pyramidal geometry, which agrees well with our experimental findings; we also find that Cu(II) facilitates water adsorption on the CeO2(110) surface. We further show that at a critical concentration of water molecules is required for the hydrolysis of water on Cu(OH)2/CeO2(110) and on pristine CeO2(110) surfaces.	Aug 2017
B18-Core EXAFS	Tandem site- and size-controlled Pd nanoparticles for the directed hydrogenation of furfural Scott M. Rogers , C. Richard A. Catlow , Carine E. Chan-Thaw , Arunabhiram Chutia , Nan Jian , Richard E. Palmer , Michal Perdjon , Adam Thetford , Nikolaos Dimitratos , Alberto Villa , Peter Wells Acs Catalysis DOI: 10.1021/acscatal.6b03190 Diamond Proposal Number(s): [10306] Open Access Show Abstract ▼ Abstract: The conversion of biomass to useful chemical products requires precise catalytic properties to achieve the required activity, selectivity and durability. Here we show, through optimized colloidal synthesis, the tandem control of Pd size and site availability for the directed hydrogenation of the bio-derived intermediate, furfural. Adjusting the temperature of colloidal reduction dictates the size of Pd nanoparticles; in some instances ultra small clusters <20 atoms are achieved. Whereas, changing the solvent system, affects the PVA-Pd interaction and relative proportion of available surface sites (corners, edges, planes), allowing us to control the selectivity to the valuable hydrogenation products of furfuryl alcohol and tetrahydrofurfuryl alcohol. We demonstrate, through combined experimental and computational studies, that Pd nanoparticle planes are more prone to deactivation through the formation of Pd carbide, and the resulting reduced efficacy of furfural binding. This approach to nanoparticle optimization is an important strategy for producing long lasting, high performance catalysts for emerging sustainable technologies.	Jan 2017
	Adsorption of formate species on Cu(h,k,l) low index surfaces Arunabhiram Chutia , Ian P. Silverwood , Matthew R. Farrow , David O. Scanlon , Peter P. Wells , Michael Bowker , Stewart F. Parker , C. Richard A. Catlow Surface Science 653, 45 - 54 DOI: 10.1016/j.susc.2016.05.002 Open Access Show Abstract ▼ Abstract: We report a density functional theory study on the relative stability of formate species on Cu(h,k,l) low index surfaces using a range of exchange-correlation functionals. We find that these functionals predict similar geometries for the formate molecule adsorbed on the Cu surface. A comparison of the calculated vibrational transition energies of a perpendicular configuration of formate on Cu surface shows an excellent agreement with the experimental spectrum obtained from inelastic neutron spectroscopy. From the calculations on adsorption energy we find that formate is most stable on the Cu(110) surface as compared to Cu(111) and Cu(100) surfaces. Bader analysis shows that this feature could be related to the higher charge transfer from the Cu(110) surface and optimum charge density at the interfacial region due to bidirectional electron transfer between the formate and the Cu surface. Analysis of the partial density of states finds that in the –5.5 eV to –4.0 eV region, hybridization between O p and the non-axial Cu dyz and dxz orbitals takes place on the Cu(110) surface, which is energetically more favourable than on the other surfaces.	Nov 2016
B18-Core EXAFS	Design and control of Lewis acid sites in Sn-substituted microporous architectures Mohammed Khaled , Arunabhiram Chutia , June Callison , Peter Philip Wells , Emma Gibson , Andrew Michael Beale , C Richard A Catlow , Robert Raja Journal Of Materials Chemistry A DOI: 10.1039/C5TA10283A Diamond Proposal Number(s): [10306] Show Abstract ▼ Abstract: Monometallic and bimetallic tin-containing framework architectures have been prepared by hydrothermal methods. Structural and spectroscopic techniques were used to probe the nature of the solid-acid sites, at the molecular level, using a combination of XRD, DR UV-Vis, solid state MAS NMR (119Sn, 27Al and 31P) and XAFS. The nature and strength of the solid-acid sites were experimentaly probed by FT-IR spectroscopy using CD3CN as a probe molecule. To elucidate further the local-structure, the structural characteristics of the Sn sites were probed using DFT calculations, with a view to rationalising the experimental findings. These detailed structural and spectroscopic studies revealed the presence of multiple Sn environments, with the monometallic SnAlPO-5 catalyst displaying a greater number of tetrahedral Sn(IV) active centres. These framework Sn(IV) centres generated stong Lewis acid sites, when compared with their bimetallic Co-Sn analogue, thereby affording attractive possibilities for modulating catalytic reactivity.	Mar 2016
B22-Multimode InfraRed imaging And Microspectroscopy	Towards microfluidic reactors for in situ synchrotron infrared studies I. Silverwood , N. Al-Rifai , E. Cao , D. Nelson , A. Chutia , P. Wells , S. P. Nolan , M. D. Frogley , G. Cinque , A. Gavriilidis , C. R. A. Catlow Review Of Scientific Instruments 87 DOI: 10.1063/1.4941825 PMID: 26931867 Diamond Proposal Number(s): [8962] Show Abstract ▼ Abstract: Anodically bonded etched siliconmicrofluidic devices that allow infrared spectroscopic measurement of solutions are reported. These extend spatially well-resolved in situ infrared measurement to higher temperatures and pressures than previously reported, making them useful for effectively time-resolved measurement of realistic catalytic processes. A data processing technique necessary for the mitigation of interference fringes caused by multiple reflections of the probe beam is also described.	Feb 2016

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