I22-Small angle scattering & Diffraction
labSAXS-Offline SAXS and Sample Environment Development
|
Diamond Proposal Number(s):
[37204, 37731]
Open Access
Abstract: Polyester thermoplastic elastomers are promising sustainable materials but their mechanical properties need improvement, in particular, attempts to increase strength often result in compromised elasticity. Strong and tough elastomers are known but require complex polymer formulations together with control over cross-linking or crystallinity, both of which challenge recycling. Here, the introduction of transient strain-stiffening approaches into fully amorphous structures show both strengthening and toughening of elastomers while conserving recyclability. The new amorphous block polyester elastomers are prepared by controlled polymerization methods using commercial monomers. The block polymers comprise a central poly(ɛ-caprolactone-co-ɛ-decalactone) block flanked by poly(cyclohexene oxide-alt-phthalate) blocks. Elastomer thermomechanical properties are tuned by varying ratios of ɛ-caprolactone to ɛ-decalactone within the mid-block to access materials with excellent mechanical properties. The best elastomers feature 30–50 wt.% polycaprolactone and exhibit tensile strengths up to 40 MPa, elongations at break above 2000%, with excellent elastic recovery (>90%). These materials exhibit strain-induced crystallization and outperform current commercial elastomers, entering a new region of tensile mechanical property space. They have service temperature ranges from −60 to 140 °C and high temperature stability (≥300 °C), with wide thermal (re)processing windows. These new polyester elastomers also show high resistance to creep, humidity resistance, and excellent recyclability.
|
Apr 2025
|
|
I22-Small angle scattering & Diffraction
|
Diamond Proposal Number(s):
[23642]
Open Access
Abstract: Despite increasing knowledge about the mechanistic aspects of lipid nanoparticles (LNPs) as oligonucleotide carriers, the structure-function relationship in LNPs has been generally overlooked. Understanding this correlation is critical in the rational design of LNPs. Here, a materials characterization approach is utilized, applying structural information from small-angle X-ray scattering experiments to design novel LNPs focusing on distinct lipid organizations with a minimal compositional variation. The lipid phase structures are characterized in these LNPs and their corresponding bulk lipid mixtures with small-angle scattering techniques, and the LNP-cell interactions in vitro with respect to cytotoxicity, hemolysis, cargo delivery, cell uptake, and lysosomal swelling. An LNP is identified that outperforms Onpattro lipid composition using lipid components and molar ratios which differ from the gold standard clinical LNPs. The base structure of these LNPs has an inverse micellar phase organization, whereas the LNPs with inverted hexagonal phases are not functional, suggesting that this phase formation may not be needed for LNP-mediated oligonucleotide delivery. The importance of stabilizer choice for the LNP function is demonstrated and super-resolution microscopy highlights the complexity of the delivery mechanisms, where lysosomal swelling for the majority of LNPs is observed. This study highlights the importance of advanced characterization for the rational design of LNPs to enable the study of structure-function relationships.
|
Mar 2025
|
|
I22-Small angle scattering & Diffraction
|
Xiaochen
Yang
,
Zhiming
Feng
,
Mustafa
Alshurafa
,
Ming
Yu
,
Andrew B.
Foster
,
Heng
Zhai
,
Tianmu
Yuan
,
Yiheng
Xiao
,
Carmine
D'Agostino
,
Ling
Ai
,
Maria
Perez-Page
,
Keenan
Smith
,
Fabrizia
Foglia
,
Adam
Lovett
,
Thomas S.
Miller
,
Jianuo
Chen
,
Peter M.
Budd
,
Stuart M.
Holmes
Diamond Proposal Number(s):
[36267]
Open Access
Abstract: High-temperature proton exchange membrane fuel cells (HT-PEMFCs) is regarded as a promising energy conversion system owing to simplified water management and enhanced tolerance to fuel impurities. However, phosphoric acid (PA) leaching remains a critical issue, diminishing energy density and durability, posing significant obstacle to the commercial development of HT-PEMFCs. To address this, composite membranes incorporating the carboxylic acid-modified polymer of intrinsic microporosity (cPIM-1) are designed as framework polymer, blended with polyvinylpyrrolidone (PVP) for HT-PEMFCs. The Lewis acid-base interactions between cPIM-1 and PVP created an extensive hydrogen-bonding network, improving membrane compatibility. The optimized microporous structure and multiple anchoring sites gave rise to “domain-limited” PA clusters, enhancing the capillary effect. Simultaneously, improved hydrophobicity synergistically optimizes catalytic interface, promoting continuous and stable proton transfer. The HT-PEMFCs based on PVP/cPIM-1 composite membrane achieved a peak power density of 1090.0 mW cm−2 at 160 °C, representing a 152% improvement compared to PVP/PES membrane. Additionally, it demonstrated excellent durability, with a voltage decay of 0.058 mV h−1 over 210 h of accelerated stress test corresponds to more than 5000 h of constant current density durability test. This study presents a promising strategy for the development of high-performance and durable novel membranes in various energy conversion systems.
|
Mar 2025
|
|
I18-Microfocus Spectroscopy
|
Open Access
Abstract: Understanding magnetic domain wall (DW) dynamics is vital for improving the performance of heavy metal/ferromagnet based spintronic devices. Pd/Co/Pd multilayers hosting perpendicular magnetic anisotropy and interfacial Dzyaloshinskii-Moriya interaction are prototypes for high density magnetic memory devices. This work presents the creep regime DW dynamics in Pd/Co/Pd trilayers with Ta buffer layer excited by symmetric field-induced domain wall motion using Kerr microscopy. A systematic increment of DW velocity with increasing Co thickness is observed. SQUID-VSM measurements reveal that the effective anisotropy constant decreases with the Co layer, leading to an increased DW width. Kerr microscopy images confirm that the DW is becoming rougher with magnetic layer thickness because of the dominance of magnetostatic energy over the DW energy. Hard X-ray photoemission spectroscopy (HAXPES) reveals the presence of alloying at interfaces of Co/Pd. The asymmetry in magnetic circular dichroism HAXPES at the Pd 3d edge pictures the induced magnetic moment in Pd which is consistent with the larger saturation magnetization obtained from vibrating sample magnetometry. Extended X-ray absorption fine structure performed in out-of-plane and in-plane geometry shows the disordered nature of the Co local environment with the interdiffusion of Pd atoms into Co causing an asymmetry in the bonds.
|
Feb 2025
|
|
I05-ARPES
|
Cong
Li
,
Yang
Wang
,
Jianfeng
Zhang
,
Guowei
Liu
,
Hongxiong
Liu
,
Wanyu
Chen
,
Hanbin
Deng
,
Wenbo
Ma
,
Craig
Polley
,
Balasubramanian
Thiagarajan
,
Timur K.
Kim
,
Jiaxin
Yin
,
Youguo
Shi
,
Tao
Xiang
,
Oscar
Tjernberg
Diamond Proposal Number(s):
[34265]
Open Access
Abstract: Non-Hermitian physics, studying systems described by non-Hermitian Hamiltonians, reveals unique phenomena not present in Hermitian systems. Unlike Hermitian systems, non-Hermitian systems have complex eigenvalues, making their effects less directly observable. Recently, significant efforts have been devoted to incorporating the non-Hermitian effects into condensed matter physics. However, progress is hindered by the absence of a viable experimental approach. Here, the discovery of the surface-selectively spontaneous reconstructed Weyl semimetal NdAlSi provides a feasible experimental platform for studying non-Hermitian physics. Utilizing angle-resolved photoemission spectroscopy (ARPES) measurements, surface-projected density functional theory (DFT) calculations, and scanning tunneling microscopy (STM) measurements, it is demonstrated that surface reconstruction in NdAlSi alters surface Fermi arc (SFA) connectivity and generates new isolated non-topological SFAs (NTSFAs) by introducing non-Hermitian terms. The surface-selective spontaneous reconstructed Weyl semimetal NdAlSi can be viewed as a Hermitian bulk – non-Hermitian boundary system. The isolated non-topological SFAs on the reconstructed surface act as a loss mechanism and open boundary condition (OBC) for the topological electrons and bulk states, serving as non-Hermitian boundary states. This discovery provides a good experimental platform for exploring new physical phenomena and potential applications based on boundary non-Hermitian effects, extending beyond purely mathematical concepts. Furthermore, it provides important enlightenment for constructing topological photonic crystals with surface reconstruction and studying their topological properties.
|
Feb 2025
|
|
B07-B1-Versatile Soft X-ray beamline: High Throughput ES1
B18-Core EXAFS
|
Abstract: The energy density of layered oxides of Li-ion batteries can be enhanced by inducing oxygen redox through replacing transition metal (TM) ions with Li ions in the TM layer. Undesirably, the cathodes always suffer from unfavorable structural degradation, which is closely associated with irreversible TM migration and slab gliding, resulting in continuous capacity and voltage decay. Herein, attention is paid to the Li ions in the TM layer (LiTM) and find their extra effects beyond inducing oxygen redox, which has been rarely mentioned. With the aid of 7Li solid-state NMR and density functional theory (DFT) calculations, the controllable migration of LiTM is verified. The mystery is uncovered that the preferential migration of LiTM plays an imperative role in preventing the structural transformation by postponing the slab gliding of the layered structure. Integrated with the inhibited TM migration, the structural robustness and reversibility of Li2RuO3 can be drastically improved after Zr-substitution, providing a solid foundation for achieving ultra-stable electrochemical performance even after thousands of cycles (2500 cycles). The discovery highlights the significance of LiTM with respect to the structural robustness and provides a potential route toward high-energy-density Li-ion batteries.
|
Jan 2025
|
|
I14-Hard X-ray Nanoprobe
|
Ruwei
Chen
,
Yunpeng
Zhong
,
Peie
Jiang
,
Hao
Tang
,
Fei
Guo
,
Yuhang
Dai
,
Jie
Chen
,
Jingyi
Wang
,
Jiyang
Liu
,
Song
Wei
,
Wei
Zhang
,
Wei
Zong
,
Fangjia
Zhao
,
Jichao
Zhang
,
Zhengxiao
Guo
,
Xiaohui
Wang
,
Guanjie
He
Diamond Proposal Number(s):
[36785]
Open Access
Abstract: Long-standing challenges including notorious side reactions at the Zn anode, low Zn anode utilization, and rapid cathode degradation at low current densities hinder the advancement of aqueous zinc-ion batteries (AZIBs). Inspired by the critical role of capping agents in nanomaterials synthesis and bulk crystal growth, a series of capping agents are employed to demonstrate their applicability in AZIBs. Here, it is shown that the preferential adsorption of capping agents on different Zn crystal planes, coordination between capping agents and Zn2+ ions, and interactions with metal oxide cathodes enable preferred Zn (002) deposition, water-deficient Zn2+ ion solvation structure, and a dynamic cathode-electrolyte interface. Benefiting from the multi-functional role of capping agents, dendrite-free Zn plating and stripping with an improved Coulombic efficiency of 99.2% and enhanced long-term cycling stability are realized. Remarkable capacity retention of 91% is achieved for cathodes after more than 500 cycles under a low current density of 200 mA g−1, marking one of the best cycling stabilities to date. This work provides a proof-of-concept of capping agents in manipulating electrochemical behaviors, which should inspire and pave a new avenue of research to address the challenges in practical energy storage beyond AZIBs.
|
Jan 2025
|
|
I19-Small Molecule Single Crystal Diffraction
|
Gaël
Bastien
,
Dalibor
Repček
,
Adam
Eliáš
,
Andrej
Kancko
,
Quentin
Courtade
,
Tetiana
Haidamak
,
Maxim
Savinov
,
Viktor
Bovtun
,
Martin
Kempa
,
Karel
Carva
,
Michal
Vališka
,
Petr
Doležal
,
Marie
Kratochvílová
,
Sarah A.
Barnett
,
Petr
Proschek
,
Jan
Prokleška
,
Christelle
Kadlec
,
Petr
Kužel
,
Ross H.
Colman
,
Stanislav
Kamba
Diamond Proposal Number(s):
[33159]
Open Access
Abstract: The study of magnetic frustration in classical spin systems is motivated by the prediction and discovery of classical spin liquid states. These uncommon magnetic phases are characterized by a massive degeneracy of their ground state implying a finite magnetic entropy at zero temperature. While the classical spin liquid state is originally predicted in the Ising triangular lattice antiferromagnet in 1950, this state has never been experimentally observed in any triangular magnets. The discovery of an electric analogue of classical spin liquids on a triangular lattice of uniaxial electric dipoles in EuAl12O19 is reported here. This new type of frustrated antipolar phase is characterized by a highly-degenerate state at low temperature implying an absence of long-range antiferroelectric order, despite short-range antipolar correlations. Its dynamics are governed by a thermally activated process, slowing down upon cooling toward a complete freezing at zero temperature.
|
Oct 2024
|
|
I15-1-X-ray Pair Distribution Function (XPDF)
|
Zefu
Huang
,
Shijian
Wang
,
Xin
Guo
,
Frederick
Marlton
,
Yameng
Fan
,
Wei-Kong
Pang
,
Tao
Huang
,
Jun
Xiao
,
Dongfang
Li
,
Hao
Liu
,
Qinfen
Gu
,
Cheng-Chieh
Yang
,
Chung-Li
Dong
,
Bing
Sun
,
Guoxiu
Wang
Diamond Proposal Number(s):
[36852]
Abstract: Sodium-ion batteries (SIBs) with low cost and environmentally friendly features have recently attracted significant attention for renewable energy storage. Sodium layer oxides stand out as a type of promising cathode material for SIBs owing to their high capacity, good rate performance, and high compatibility for manufacturing. However, the poor cycling stability of layer oxide cathodes due to structure distortion greatly impacts their practical applications. Herein, a high entropy doped Cu, Fe, and Mn-based layered oxide (HE-CFMO), Na0.95Li0.05Mg0.05Cu0.20Fe0.22Mn0.35Ti0.13O2 for high-performance SIBs, is designed. The HE-CFMO cathode possesses high-entropy transition metal (TM) layers with a homogeneous stress distribution, providing a moderated interlayer spacing to maintain the structure stability and enhance Na+ ion diffusion. In addition, Li doping in TM layers increases the Mn valence state, which effectively suppresses John–Teller effect, thus stabilizing the layered structure during cycling. Furthermore, the use of nontoxic and low-cost raw materials benefits future commercialization and reduces the risk of environmental pollution. As a result, the HE-CFMO cathode exhibits a super cycling performance with a 95% capacity retention after 300 cycles. This work provides a promising strategy to improve the structure stability and reaction kinetics of cathode materials for SIBs.
|
Oct 2024
|
|
I09-Surface and Interface Structural Analysis
|
Megan O.
Hill
,
Ji Soo
Kim
,
Moritz L.
Müller
,
Dibya
Phuyal
,
Sunil
Taper
,
Manisha
Bansal
,
Maximilian T.
Becker
,
Babak
Bakhit
,
Tuhin
Maity
,
Bartomeu
Monserrat
,
Giuliana Di
Martino
,
Nives
Strkalj
,
Judith L.
Macmanus‐driscoll
Diamond Proposal Number(s):
[31918]
Open Access
Abstract: The discovery of ferroelectricity in nanoscale hafnia-based oxide films has spurred interest in understanding their emergent properties. Investigation focuses on the size-dependent polarization behavior, which is sensitive to content and movement of oxygen vacancies. Though polarization switching and electrochemical reactions is shown to co-occur, their relationship remains unclear. This study employs X-ray photoelectron spectroscopy with depth sensitivity to examine changes in electrochemical states occurring during polarization switching. Contrasting Hf0.5Zr0.5O2 (HZO) with Hf0.88La0.04Ta0.08O2 (HLTO), a composition with an equivalent structure and comparable average ionic radius, electrochemical states are directly observed for specific polarization directions. Lower-polarization films exhibit more significant electrochemical changes upon switching, suggesting an indirect relationship between polarization and electrochemical state. This research illuminates the complex interplay between polarization and electrochemical dynamics, providing evidence for intrinsic polar states in HfO2-based ferroelectrics.
|
Sep 2024
|
|
