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A systematic investigation into the structure and properties of five commercially available nickel-based soft magnetic materials was carried out. The five systems are Fe23Ni77, Fei6Ni77Cu7, Fei6Ni77Cu5Cr2, Fei6Ni77Mo7 and Fei6Ni77Nb7. These alloy systems were processed by ball milling to obtain the compound with grain size of several tens of nanometers in length scale. Depending on the exact chemical composition, some amorphous or semi-amorphous phases were deposited at the inter-granular layers as evidenced from the TEM micrographs. As the grain size decreases to several tens of nanometer in scale, results of the ball milled powders showed that the all the five systems exhibited coercivities that increased with grain size, contrary to the random anisotropy model. These were attributed to the internal stress generated from the mechanical forces. Stress-annealed magnets sintered from the alloyed powders showed strong dependency of the anisotropy on grain size where the coercivity decreases with grain size. The effect of alloying elements on the magnetic properties of these nanostructured magnets suggest that it is less significant compared to the effect on grain size. Although the coercivity varies with the alloying elements, the critical factor on its behaviour is dominated by the grain / particle size.

Ion adsorption inside electrified carbon micropores is pivotal for the operation of supercapacitors. Depending on the electrolyte, two main mechanisms have been identified so far, the desolvation of ions in solvents and the formation of superionic states in ionic liquids. Here, it is shown that upon confinement inside negatively charged micropores, transition-metal cations dissolved in water associate to form oligomer species. They are identified using in situ X-ray absorption spectroscopy. The cations associate one with each other via hydroxo bridging, forming ionic oligomers under the synergic effect of spatial confinement and Coulombic screening. The oligomers display sluggish dissociation kinetics and accumulate upon cycling, which leads to supercapacitor capacitance fading. They may be dissolved by applying a positive potential, so an intermittent reverse cycling strategy is proposed to periodically evacuate micropores and revivify the capacitance. These results reveal new insights into ion adsorption and structural evolution with their effects on the electrochemical performance, providing guidelines for designing advanced supercapacitors. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version This work was supported by Singapore Ministry of Education Academic Research Fund Tier 2 (Grant No. MOE-T2EP10220-0005), Academic Research Fund Tier 1 (Grant No. RG104/18), Singapore National Research Foundation (Nanomaterials for Energy and Water Management CREATE Programme), Energy Innovation Research Programme (EIRP) (Grant No. NRF2015EWT-EIRP002-008), and French National Research Agency (Labex STORE-EX, Grant No. ANR-10-LABX-0076).

The rise of electronic waste (e-waste) generation around the globe has become a major concern in recent times and its recycling is mostly focused on the recovery of valuable metals, such as gold, silver, and copper, etc. However, e-waste consists of a significant weight fraction of plastics (25-30%) which are either discarded or incinerated. There is a growing need for recycling of these e-waste plastics. The majority of them are made from high-quality polymers (composites), such as acrylonitrile butadiene styrene (ABS), high impact polystyrene (HIPS), polycarbonate (PC), polyamide (PA), polypropylene (PP) and epoxies. These plastics are often contaminated with hazardous materials, such as brominated flame retardants (BFRs) and heavy metals (such as Pb and Hg). Under any thermal stress (thermal degradation), the Br present in the e-waste plastics produces environmentally hazardous pollutants, such as hydrogen bromide or polybrominated diphenyl ethers/furans (PBDE/Fs). The discarded plastics can lead to the leaching of toxins into the environment. It is important to remove the toxins from the e-waste plastics before recycling. This review article gives a detailed account of e-waste plastics recycling and recovery using thermochemical processes, such as extraction (at elevated temperature), incineration (combustion), hydrolysis, and pyrolysis (catalytic/non catalytic). A basic framework of the existing processes has been established by reviewing the most interesting findings in recent times and the prospects that they open in the field recycling of e-waste plastics. Ministry of National Development (MND) National Environmental Agency (NEA) National Research Foundation (NRF) Authors would like to thank financial support from National Research Foundation, Prime Minister’s Office, Singapore, the Ministry of National Development, Singapore, and National Environment Agency, Ministry of Sustainability and the Environment, Singapore under the Closing the Waste Loop R&D Initiative as part of the Urban Solutions & Sustainability e Integration Fund (Award No. USS-IF-2018-4).

International audience; In nanomedicine, the widespread concern of nanoparticles in general, and dendrimers, in particular, is the analysis of key in-vivo physicochemical parameters to ensure the preclinical and clinical development of ‘safe’ bioactive nanomaterials. It is clear that for biomedical applications, biocompatible dendrimers, used as nanocarriers or active per se, should be devoid of toxicity and immunogenicity, and have adequate PK/PD behaviors (adequate exposure) in order to diffuse in different tissues. Functionalization of dendrimers has a dramatic effect on in-vivo physicochemical parameters. In this review, we highlighted key in-vivo physicochemical properties, based on data from biochemical, cellular and animal models, to provide biocompatible dendrimers. Up-to-date, only scarce studies have been described on this topic.

The huge consumption of modern plastic with improper disposals has posed a great threat to the environment and human beings. To put these post-consumer plastics into the recycling chain, laser induced breakdown spectroscopy (LIBS) has been established as a potential tool for rapid grading of plastics online. Meanwhile, LIBS is a powerful tool for plastic investigations in the laboratory with the capacity of simultaneous qualitative and quantitative analysis. The present review describes the development and prospect of plastic investigations using LIBS, highlighting the intrinsic advantages of LIBS for plastic recycling. Moreover, the selection of hardware components and analysis methods are discussed, which may help to start a research on plastic using LIBS. National Environmental Agency (NEA) National Research Foundation (NRF) The authors are grateful for the financial support from SCARCE, which is supported by the National Research Foundationgs2:, Prime Minister's Office, Singapore, the Ministry of National Development, Singapore, and National Environment Agency, Ministry of Sustainability and the Environment, Singapore under the Closing the Waste Loop R&D Initiative as part of the Urban Solutions & Sustainability - Integration Fund (Award No. USS-IF-2018-4).

International audience; Digital light processing technique was applied to manufacture alumina ceramic parts with two types of lattice structure units, i.e. vertex interconnect structure and edge structure. The internal porosity of the unit is 40%. The printed parts were sintered and the grain size is about 1.1 μm. The bending strength of the vertex interconnect structure is much larger than that of the edge structure. Materials genome initiative (MGI) aims to digital design and intelligent manufacture for advanced components. This research shows us an example to achieve this goal.

In nanomedicine, the widespread concern of nanoparticles in general, and dendrimers, in particular, is the analysis of key in-vivo physicochemical parameters to ensure the preclinical and clinical development of ‘safe’ bioactive nanomaterials. It is clear that for biomedical applications, biocompatible dendrimers, used as nanocarriers or active per se, should be devoid of toxicity and immunogenicity, and have adequate PK/PD behaviors (adequate exposure) in order to diffuse in different tissues. Functionalization of dendrimers has a dramatic effect on in-vivo physicochemical parameters. In this review, we highlighted key in-vivo physicochemical properties, based on data from biochemical, cellular and animal models, to provide biocompatible dendrimers. Up-to-date, only scarce studies have been described on this topic.

Non-graphitized carbon (NGC) has been extensively utilized as carbonaceous anode in sodium-ion batteries (SIBs). However, more optimization to achieve competitive capacity and stability is still challenging for SIBs. In the study, the dopant strategy is utilized to construct nitrogen/sulfur-doped non-graphitized carbon (N-NGC or S-NGC) shell decorated on three-dimensional graphene foam (GF) as a self-support electrode. The highly disordered microstructures of heteroatom doped carbons are produced by applying a low-temperature pyrolysis treatment to precursors containing nitrogen and sulfur. The DFT calculations of Na-ion adsorption energies at diverse heteroatom sites show marginal-S, pyrrolic N and pyridinic N with more intensive Na-ion adsorption ability than middle-S, C[dbnd]O and pristine carbon. The N-NGC with dominant small graphitic regions delivers adsorption ability to Na-ion, while the S-NGC with significant single carbon lattice stripes demonstrates redox reaction with Na-ion. Evidently, in comparison with only adsorption-driven slope regions at high potential for N-NGC, the redox reaction-generated potential-plateau enables non-graphitized S-NGC superior discharge/charge capacity and cycle-stability in the slope region. This work could provide deep insight into the rational design of non-graphitized carbon with rich microstructure and composition. This work was supported by the National Natural Science Foundation of China (52272296, 51502092), the Fundamental Research Funds for the Central Universities (JKD01211601, 1222201718002), the National Overseas High-Level Talent Youth Program in China, and the Eastern Scholar Project of Shanghai.

International audience; At the intersection between treatment and diagnosis, nanoparticles technologies are strongly impacting the development of both therapeutic and diagnostic agents. Consequently, the development of novel modalities for concomitant noninvasive therapy and diagnostics known as theranostics as a single platform has gained significant interests. These multifunctional theranostic platforms include carbon-based nanomaterials (e.g., carbon nanotubes), drug conjugates, aliphatic polymers, micelles, vesicles, core-shell nanoparticles, microbubbles and dendrimers bearing different contrast agents and drugs, such as cytotoxic compounds in the oncology domain. Dendrimers emerged as a new class of highly tunable hyperbranched polymers, and have been developed as useful theranostic platforms. Magnetic resonance imaging, gamma scintigraphy, computed tomography and optical imaging are the main techniques developed with dendrimers in the theranostic domain in oncology. Different imaging agents have been used such as Gd(III), 19F, Fe2O3 (MRI), 76Br (PET), 111In, 88Y, 153Gd, 188Re, 131I (SPECT), 177Lu, gold (CT) and boronated groups, siliconnaphthalocyanines, dialkylcarbocyanines and QDs (optical imaging dyes).

The stomatopod is a fascinating animal that uses its weaponized appendage dactyl clubs for breaking mollusc shells. Dactyl clubs are a well studied example of biomineralized hierarchical structures. Most research has focused on the regions close to the action, namely the impact region and surface composed of chitin and apatite crystallites. Further away from the site of impact, the club has lower mineralization and more amorphous phases; these areas have not been as actively studied as their highly mineralized counterparts. This work focuses on the side of the club, in what is known as the periodic and striated regions. A combination of laboratory micro-computed tomography, synchrotron X-ray diffraction mapping and synchrotron X-ray fluorescence mapping has shown that the mineral in this region undergoes the transition from an amorphous to a crystalline phase in some, but not all, clubs. This means that this side region can be mineralized by either an amorphous phase, calcite crystallites or a mixture of both. It was found that when larger calcite crystallites form, they are organized (textured) with respect to the chitin present in this biocomposite. This suggests that chitin may serve as a template for crystallization when the side of the club is fully mineralized. Further, calcite crystallites were found to form as early as 1 week after moulting of the club. This suggests that the side of the club is designed with a significant safety margin that allows for a variety of phases, i.e. the club can function independently of whether the side region has a crystalline or amorphous mineral phase. Published version We thank the Danish Agency for Science, Technology and Innovation for funding the instrument center DanScatt. We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Beam time was allocated for proposal I20180923EC. The research leading to this result has been supported by the project CALIPSOplus from the EU Framework Programme for Research and Innovation HORIZON 2020 (grant no. 730872). We thank Alexander Bernthz Jensen, Kristine Hjerrild Neldeborg, Jonas Palle and Maja Østergaard for help with measuring data on P06 at Petra III. We acknowledge the MAX IV Laboratory for time on Beamline DanMAX (proposal no. 20210507). Research conducted at MAX IV, a Swedish national user facility, is supported by the Swedish Research council (contract no. 2018-07152), the Swedish Governmental Agency for Innovation Systems (contract no. 2018-04969) and Formas (contract no. 2019-02496). DanMAX is funded by NUFI (grant no. 4059- 00009B). We thank Peter Alling Strange Vibe for assistance with measuring data at DanMAX. Use of the Novo Nordisk Foundation research infrastructure AXIA (grant no. NNF19OC0055801) is gratefully acknowledged. We acknowledge support from the ESS lighthouse on hard materials in 3D, SOLID, funded by the Danish Agency for Science and Higher Education (grant no. 8144-00002B).

High-mobility van der Waals ambipolar semiconductors are promising in logic and reconfigurable circuits, integrated optoelectronic circuits, due to the excellent gate-controlled capability and effectively tunability of major charge carriers by electrostatic field. Controllable growth of high-quality ambipolar semiconductors with high mobility and stability is highly glamorous and indispensable for further research. Here, we demonstrate a straightforward space-confined chemical vapor deposition (CVD) method to synthesize high-quality quasi-one-dimensional (1D) tellurium (Te) nanoribbons (NRs). By introducing H2 into the gas flow, endothermic compound H2Te was generated from the reaction of liquid Te with H2, and consequently decomposed into elemental Te at low temperature. Further, the Te NRs have been utilized for in-situ fabrication of field-effect transistors (FETs) without transferring process. Ambipolar features are achieved using nickel (Ni) as an ohmic contact. More importantly, the mobilities of the Te NR transistor for hole/electron are as high as 1755/28.6 cm2V−1s−1 and 4024/278 cm2V−1s−1 at room temperature and under a temperature below 20 K, respectively. Our findings confirm the novel strategy for synthesizing 1D elemental semiconductors and their applications with ambipolar behaviors. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) Submitted/Accepted version The authors gratefully acknowledge financial support by National Key Research and Development Program of China (2020YFB2008501), the National Natural Science Foundation of China (61974120 and 11904289), Key Research and Development Program of Shaanxi Province (2020ZDLGY04-08, 2020GXLH-Z-027, and 2021JZ-43), the Natural Science Foundation of Shaanxi Province (2023-JC-YB-495 and 2022JQ-659), the Key Program for International Science and Technology Cooperation Projects of Shaanxi Province (2018KWZ-08), the Natural Science Foundation of Ningbo (202003N4003), the Fundamental Research Funds for the Central Universities (3102019PY004, 31020190QD010, and 3102019JC004), the start-up funds from Northwestern Polytechnical University, and open research fund of the State Key Laboratory of Organic Electronics and Information Displays. This work was also supported by National Research Foundation–Competitive Research Program NRF-CRP22-2019-0007 and NRF-CRP21-2018-0007, and supported by A*STAR under its AME IRG Grant (Project No. A2083c0052).

The progression of green technologies has driven higher future demands for valuable metals such as lithium, cobalt, nickel, and manganese, hence necessitating the recycling of lithium-containing energy storage systems. Restrategizing conventional metal recycling technologies with sustainable biological approaches can explore the potential to curtail expensive process costs and emissions of hazardous by-products. This article advocates the benefits and persuasion for future studies and applications to exploit current concepts of microbial-based metal recycling technologies as environmentally cleaner options. National Environmental Agency (NEA) National Research Foundation (NRF) Submitted/Accepted version This research/project is supported by the National Research Foundation, Singapore, and National Environment Agency, Singapore, under its Closing the Waste Loop Funding Initiative (award no. USSIF- 2018-4).

Two-dimensional (2D) materials including graphene, transition metal dichalcogenides, black phosphorus, MXenes, and semimetals have attracted extensive and widespread interest over the past years for their many intriguing properties and phenomena, underlying physics, and great potential for applications. The vast library of 2D materials and their heterostructures provides a diverse range of electrical, photonic, mechanical, and chemical properties with boundless opportunities for photonics and plasmonic devices. The infrared (IR) regime, with wavelengths across 0.78 μm to 1000 μm, has particular technological significance in industrial, military, commercial, and medical settings while facing challenges especially in the limit of materials. Here, we present a comprehensive review of the varied approaches taken to leverage the properties of the 2D materials for IR applications in photodetection and sensing, light emission and modulation, surface plasmon and phonon polaritons, non-linear optics, and Smith-Purcell radiation, among others. The strategies examined include the growth and processing of 2D materials, the use of various 2D materials like semiconductors, semimetals, Weyl-semimetals and 2D heterostructures or mixed-dimensional hybrid structures, and the engineering of light-matter interactions through nanophotonics, metasurfaces, and 2D polaritons. Finally, we give an outlook on the challenges in realizing high-performance and ambient-stable devices and the prospects for future research and large-scale commercial applications. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) This work is partially supported by the National Research Foundation, Singapore, under its CRP program (NRF-CRP26- 2021-0004) and A*STAR AME IRG (A20E5c0084). Z.L. acknowledges the support from PHC Merlion Program 2020. L.W. gratefully acknowledges the Start-Up Research Grant from the Singapore University of Technology and Design via Grant No. SRG SMT 2021 169, and National Research Foundation Singapore via Grant Nos. NRF2021-QEP2-02-P03 and NRF2021-QEP2-03-P09. Y.L. acknowledges the support from A*STAR Career Development Fund - Seed Projects (C222812008). M.Z. acknowledges the support from A*STAR Career Development Fund (C210812027).

Three-dimensional/low-dimensional perovskite solar cells afford improved efficiency and stability. The design of low-dimensional capping materials is constrained to tuning the A-site organic cation, as Pb2+ and Sn2+ are the only options for the metal cation. Here we unlock access to a library of low-dimensional capping materials with metal cations beyond Pb2+/Sn2+ by processing a full precursor solution containing both metal and ammonium halides. This enables easier synthetic control of the low-dimensional capping layer and greater versatility for low-dimensional interface engineering. We demonstrate that a zero-dimensional zinc-based halogenometallate (PEA2ZnX4; PEA = phenethylammonium, X = Cl/I) induces more robust surface passivation and stronger n–N isotype three-dimensional/low-dimensional heterojunctions than its lead-based counterpart. We exhibit p–i–n solar cells with 24.1% efficiency (certified 23.25%). Our cells maintain 94.5% initial efficiency after >1,000 h of operation at the maximum power point. Our findings expand the material library for low-dimensional interface engineering and stabilization of highly efficient three-dimensional/low-dimensional perovskite solar cells. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version This work is supported by the Ministry of Singapore under its AcRF Tier 1 (Project RG6/21 (2021-T1-001-072) to Y.M.L.) and Tier 2 grants (MOE2019-T2-1-006 to T.C.S., MOE2019-T2-1-085 to Y.M.L. and MOE-T2EP50120-0004 to T.C.S.), and the National Research Foundation (NRF) Singapore under its NRF Investigatorship (NRF-NRFI2018-04 to T.C.S.).

Bacterial biofilms reduce the performance and efficiency of biomedical and industrial devices. The initial step in forming bacterial biofilms is the weak and reversible attachment of the bacterial cells onto the surface. This is followed by bond maturation and secretion of polymeric substances, which initiate irreversible biofilm formation, resulting in stable biofilms. This implies that understanding the initial reversible stage of the adhesion process is crucial to prevent bacterial biofilm formation. In this study, we analyzed the adhesion processes of E. coli on self-assembled monolayers (SAMs) with different terminal groups using optical microscopy and quartz crystal microbalance with energy dissipation (QCM-D) monitoring. We found that a considerable number of bacterial cells adhere to hydrophobic (methyl-terminated) and hydrophilic protein-adsorbing (amine- and carboxy-terminated) SAMs forming dense bacterial adlayers while attaching weakly to hydrophilic protein-resisting SAMs [oligo(ethylene glycol) (OEG) and sulfobetaine (SB)], forming sparse but dissipative bacterial adlayers. Moreover, we observed positive shifts in the resonant frequency for the hydrophilic protein-resisting SAMs at high overtone numbers, suggesting how bacterial cells cling to the surface using their appendages as explained by the coupled-resonator model. By exploiting the differences in the acoustic wave penetration depths at each overtone, we estimated the distance of the bacterial cell body from different surfaces. The estimated distances provide a possible explanation for why bacterial cells tend to attach firmly to some surfaces and weakly to others. This result is correlated to the strength of the bacterium-substratum bonds at the interface. Elucidating how the bacterial cells adhere to different surface chemistries can be a suitable guide in identifying surfaces with a more significant probability of contamination by bacterial biofilms and designing bacteria-resistant surfaces and coatings with excellent bacterial antifouling characteristics. Published version This work was supported by the JSPS KAKENHI grant (Grant Numbers JP22H04530, JP21H05511, and JP20H05210).

The surface-enhanced Raman scattering (SERS) bioprobe's strategy for identifying tumor cells always depended on the intensity difference of the Raman signal compared with that of normal cells. Hence, exploring novel SERS nanostructure with excellent spectra stability, a high enhancement factor (EF), and good biocompatibility is a primary premise for boosting SERS signal reliability and accuracy of tumor cells. Here, high SERS EF (5.52 × 106) is acquired by developing novel amorphous nitrogen-doped carbon (NDC) nanocages (NCs), whose EF value was in a leading position among carbon-based SERS substrates. In addition, a uniform SERS signal was obtained on NDC NCs due to homogeneous morphology and size. The delocalized carbon-conjugated systems of graphitic-N, pyrrole-N, and pyridine-N with lone pair electrons increase the electronic density of states and reduce the electron localization function of NDC NCs, thereby promoting the charge transfer process. The electron-donor platform of the NDC NCs facilitates the thermodynamic process of charge transfer, resulting in multimode vibrational coupling in the surface complexes, which greatly amplifies the molecular polarizability. Importantly, the good biocompatibility and signal stability endow these NDC NC SERS bioprobes unique superiority in distinguishing tumor cells, and quantitative recognition of two triple-negative breast cancer cells based on SERS detection mode has been successfully realized. This work was supported by the funding from National Natural Science Foundation of China (52002380, 32025021, 31971292, 52022006, 12274018, 21875008 and 32111540257), Ningbo 3315 Innovative Teams Program (2019A-14-C), the Science and Technology Bureau of Ningbo City (2020Z094), Zhejiang Province Key Research Project (2019C03058, 2020C03110), Youth Innovation Promotion Association Foundation of CAS, and Zhejiang Provincial Natural Science Foundation of China (LQ20E020003).

Fe2Ni2CrAl multi-principal elements alloy (MPEA) has been regarded as promising candidate for engineering application due to its desirable combination of strength and plasticity. In this work, the microstructure, hardness and wear resistance of Fe2Ni2CrAl MPEA were systematically investigated. This alloy has a dual-phase structure, comprised of the FCC and BCC/+B2 phase. The average nanohardness is 4.59 GPa, and the average elastic modulus is 199.4 GPa. By performing reciprocating ball-on-flat friction tests, the Fe2Ni2CrAl MPEA shows good wear resistance, with a wear rate of 8.72 × 10−5 mm3/(Nm) and average friction coefficient of ~ 0.54. The wear mechanisms are a mixture of adhesive, abrasive and oxidation wear, accompanied by cracks and delamination. Molecular dynamics (MD) was utilized to study the wear behavior at nanoscale. The surface suffers severer deformation during the first slide. Then, the reciprocating friction contributes to the surface strain hardening in the later slide. The large displacement and shear strain region were concentrated below the rigid ball, and the atomic damage was identified. Fewer dislocations are produced during reciprocating friction, accompanied with the reduced atomic shear strain and lattice deterioration. The Shockley-type dislocation plays a dominant role in the whole nano-wear process. This work explored the friction behavior in depth and provided a deep insight into wear mechanisms for Fe2Ni2CrAl MPEAs. Agency for Science, Technology and Research (A*STAR) This work is supported by AME Programmatic Fund by the Agency for Science, Technology and Research, Singapore under Grants No. A1898b0043 and A18B1b0061 and the China Scholarship Council.

The shift towards renewable energy mix has resulted in an exponential growth of the photovoltaic (PV) industry over the past few decades. Parallelly, new recycling technology developments are required to address the incoming volume of waste as they gradually approach their end-of-life (EoL) to realize the concept of a circular economy. Typical recycling processes involve high-temperature burning for separation and release of the PV cells for metal recovery processes. However, this thermal process generates gaseous by-products that cause serious health and environmental issues. Eschewing the need for burning, we demonstrate a simple crush-and-sieve methodology to strategically aids the separation of polymeric and metallic contents. The proposed approach showcased the efficient size-selective separation and generated polymer- and metal-rich fractions. More than 90 % of the total polymer present within the studied wastes was found to be retained in larger sized-particle fractions (F1 and F2). Metal content analysis highlighted the enrichment of highly valuable silver into the smallest sized-particle fraction (F4), accounting up to 70 % and 80 % of total silver present respectively for EVAc and MP. The benefits ripe through this simple crush-and-sieve method offers an attractive pathway for PV recycling process to obtain metal-rich fractions and allow focused recovery of valuable materials through an environmentally friendlier manner. National Environmental Agency (NEA) National Research Foundation (NRF) This research/project is supported by the National Research Foundation, Singapore, and National Environment Agency, Singapore under its Closing the Waste Loop Funding Initiative (Award No. USS-IF-2018- 4).

We measure the ultrafast spectral diffusion, vibronic dynamics, and energy relaxation of a CdSe colloidal quantum wells (CQWs) system at room temperature using two-dimensional electronic spectroscopy (2DES). The energy relaxation of light-hole (LH) excitons and hot carriers to heavy-hole (HH) excitons is resolved with a time scale of ∼210 fs. We observe the equilibration dynamics between the spectroscopically accessible HH excitonic state and a dark state with a time scale of ∼160 fs. We use the center line slope analysis to quantify the spectral diffusion dynamics in HH excitons, which contains an apparent sub-200 fs decay together with oscillatory features resolved at 4 and 25 meV. These observations can be explained by the coupling to various lattice phonon modes. We further perform quantum calculations that can replicate and explain the observed dynamics. The 4 meV mode is observed to be in the near-critically damped regime and may be mediating the transition between the bright and dark HH excitons. These findings show that 2DES can provide a comprehensive and detailed characterization of the ultrafast spectral properties in CQWs and similar nanomaterials. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Submitted/Accepted version H.V.D. gratefully acknowledges the financial support in part from the Singapore Agency for Science, Technology and Research (A*STAR) SERC under Grant No. M21J9b0085, and the Singapore Ministry of Education Tier 1 grant (MOERG62/20). H.V.D. also gratefully acknowledges the support from TUBA. H.-S.T. gratefully acknowledges the financial support in part from the Singapore Ministry of Education Tier 1 grant (MOE-RG2/19 and MOE-RG14/20). O.V.P. acknowledges the financial support from the United States National Science Foundation under Grant No. CHE-2154367.

Light activated carbenes provide a unique method of non-specific covalent bond formation needed in bioadhesives and rapid gelation. The highly reactive carbenes formed upon UV irradiation allow for binding to a wide range of natural and synthetic substrates in addition to cohesive bonds. However, little is known about how these crosslinkers would behave in the presence of additives, which are important for tuning material properties. This work investigates carbene based bioadhesives in the presence of various liquid additives containing reactive functional groups of hydroxyl, thiol, amine, or acrylate. Steady shear viscosity, dynamic mechanical properties, microstructure, and reactive functional groups are evaluated by photorheometry, scanning electron microscopy (SEM), and FTIR spectroscopy. The triol hydroxy additive maintains the storage modulus despite dilution of the diazirine crosslinker. The thiol additive reduces apparent viscosity whilst maintaining material properties. Polyamine accelerates ester hydrolysis and increases hydrophilicity. For the first time diacrylate polymerization is demonstrated by photoactivated diazirine, the carbene precursor. The diacrylate additive displays synergistic enhancement of dynamic modulus within the binary composite, reaching 977 kPa compared to 82 kPa of neat carbene based bioadhesive. The polymerisation of acrylates initiated by diazirine photolysis opens possibilities for acrylate initiation and hybrid composite biomaterials. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Nanyang Technological University Submitted/Accepted version T.W.J.S. and I.D. are co-inventors of patent application: Hygroscopic, Crosslinking Coatings and Bioadhesives; PCT/SG2018/050452. Authors declare no competing interests. The project was supported by A*Star IAF PP Grant (H19/01/a0/0II9): CathoGlu Bioadhesives-preventing catheter extravasation and skin infections; Ministry of Education Tier 1 Grant RG17/18 (S): Novel light activated, diazo protecting groups; Ministry of Education Tier 1 Grant RT07/20: Fiber-optic orthopaedic implants for bone-implant adhesion; Ministry of Education Tier 2 Grant (MOE2018‐T2‐2‐114): CaproGlu, Double sided wet-tissue adhesives; NTUitive POC (Gap) Fund NGF/2018/05: Aesthetic Applications of CaproGlu Bioadhesives. Figures created with BioRender.com.

Chemical recycling of poly (ethylene terephthalate) (PET) by depolymerization into monomers to recreate virgin-grade plastics is desirable; however, the energy inefficient separation and purification steps needed to obtain high-purity monomers result in poor overall economic feasibility at present. Herein, we present a one-step integrated process for partial depolymerization and upcycling of PET oligomers directly in to high-value product without any need for solvent recovery and purification. The key strategy for our approach is using multifunctional cleaving agents such as glycerol in the presence of ionic liquid as a catalyst for controlled partial depolymerization of PET via transesterification using N-Methyl-2-pyrrolidone (NMP) as solvent. The obtained depolymerized, oligomeric PET (DOPET) recyclate together with NMP and IL is a gel-like, ionic-conductive material, also termed as an “ionogel”, that has the potential to be used in energy storage applications or as mechanically robust electrical conductors. This is a one-step process requiring no extensive separation and purification of PET oligomers or distillation of solvent for recovery which further simplifies the recycling process while simultaneously increasing the value of the waste product. We have further investigated the effects of the choice and amount of cleaving agent on the molecular weight and branching of the DOPET oligomers and hence the properties of the upcycled end products. Moreover, we have also shown the versatility of the abovementioned process for controlled depolymerization of other condensation polymers such as polyamides, polyurethane, and even mixed polymer products to obtain high value functional materials. Submitted/Accepted version

Membrane technology is a key enabler for a circular pharmaceutical industry, but chemically resistant polymeric membranes for organic solvent nanofiltration (OSN) often suffer from lower-than-required performances. Recently, graphene-based laminated membranes using small-flake graphene oxide (SFGO) nanosheets open up new avenues for high-performance OSN, but their permeance toward high viscosity solvents is below expectation. To address this issue, we design hyperlooping channels using multiwalled carbon nanotubes (MWCNTs) intercalated within lanthanum(III) (La3+)-cross-linked SFGO nanochannels to form a ternary nanoarchitecture for low-resistant transport toward high viscosity solvents. At optimized MWCNT loading, the defect-free membrane exhibits 138 L m-2 h-1 bar-1 ethanol permeance at >99% rejections toward organic dyes, outperforming state-of-the-art graphene oxide (GO)-based membranes to date. Even butanol─with twice the viscosity of ethanol─exhibits a permeance no less than 60 L m-2 h-1 bar-1 at comparable rejection rates. Theoretical simulation suggests that La3+ cross-linking is critical and can create an intact architecture that brings size exclusion into play as the dominant separation mechanism. Also, MWCNT nanochannel offers at least 1.5-fold lower ethanol transport resistance than that of the GO nanochannel, owing to greater bulk freedom in orientating ethanol molecules. Overall, the hyperlooping architecture demonstrates ∼3-fold higher permeance than neat SFGO membrane for elevating OSN performances. Economic Development Board (EDB) Nanyang Technological University This work was supported by GSK-EDB Trust Fund (T.-H.B. and J.-M.L.) and the National Research Foundation of Korea (NRF) grant funded by the Korea government MSIT (T.-H.B.; Reference number: NRF-2021R1A2C3008570). K.Z. and Y.W. would like to acknowledge financial support from the Nanyang Environment and Water Research Institute (Core Fund), Nanyang Technological University, Singapore. K.G. would also like to acknowledge funding support from the Economic Development Board (EDB) of Singapore to the Singapore Membrane Technology Centre.

The development of integrated circuits (ICs) based on a complementary metal−oxide−semiconductor through transistor scaling has reached the technology bottleneck; thus, alternative approaches from new physical mechanisms are highly demanded. Valleytronics in two-dimensional (2D) material systems has recently emerged as a strong candidate, which utilizes the valley degree of freedom to process information for electronic applications. However, for all-electrical valleytronic transistors, very low room- temperature “valley on−off” ratios (around 10) have been reported so far, which seriously limits their practical applications. In this work, we successfully illustrated both n- and p-type valleytronic transistor performances in monolayer MoS2 and WSe2 devices, with measured “valley on−off” ratios improved up to 3 orders of magnitude greater compared to previous reports. Our work shows a promising way for the electrically controllable manipulation of valley degree of freedom toward practical device applications. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version This work was supported by the Singapore National Research Foundation through its Competitive Research Program (CRP Award No. NRF-CRP22-2019-0004 and Quantum engineering programme), the Singapore Ministry of Education (MOE2016-T3-1-006 (S)), and the Start-up Research Grant of University of Macau (SRG2022-00030-IAPME).

Mixed-dimensional perovskites containing mixtures of organic cations hold great promise to deliver highly stable and efficient solar cells. However, although a plethora of relatively bulky organic cations have been reported for such purposes, a fundamental understanding of the materials’ structure, composition, and phase, along with their correlated effects on the corresponding optoelectronic properties and degradation mechanism remains elusive. Herein, we systematically engineer the structures of bulky organic cations to template low-dimensional perovskites with contrasting inorganic framework dimensionality, connectivity, and coordination deformation. By combining X-ray single-crystal structural analysis with depth-profiling XPS, solid-state NMR, and femtosecond transient absorption, it is revealed that not all low dimensional species work equally well as dopants. Instead, it was found that inorganic architectures with lesser structural distortion tend to yield less disordered energetic and defect landscapes in the resulting mixed-dimensional perovskites, augmented in materials with a longer photoluminescence (PL) lifetime, higher PL quantum yield (up to 11%), improved solar cell performance and enhanced thermal stability (T80 up to 1000 h, unencapsulated). Our study highlights the importance of designing templating organic cations that yield low-dimensional materials with much less structural distortion profiles to be used as additives in stable and efficient perovskite solar cells. Ministry of Education (MOE) National Research Foundation (NRF) Published version The authors would like to acknowledge funding from the Singapore National Research Foundation through the IntraCREATE Collaborative Grant (NRF2018-ITC001-001), Energy Innovation Research Program (NRF2015EWT-EIRP003-004 and Solar CRP: S18-1176-SCRP), and MOE Tier 2 project MOE2019-T2-2-097.

Photoelectrochemical water splitting is one of the sustainable routes to renewable hydrogen production. One of the challenges to deploying photoelectrochemical (PEC) based electrolyzers is the difficulty in the effective capture of solar radiation as the illumination angle changes throughout the day. Herein, we demonstrate a method for the angle-independent capture of solar irradiation by using transparent 3 dimensional (3D) lattice structures as the photoanode in PEC water splitting. The transparent 3D lattice structures were fabricated by 3D printing a silica sol–gel followed by aging and sintering. These transparent 3D lattice structures were coated with a conductive indium tin oxide (ITO) thin film and a Mo-doped BiVO4 photoanode thin film by dip coating. The sheet resistance of the conductive lattice structures can reach as low as 340 Ohms per sq for ∼82% optical transmission. The 3D lattice structures furnished large volumetric current densities of 1.39 mA cm−3 which is about 2.4 times higher than a flat glass substrate (0.58 mA cm−3) at 1.23 V and 1.5 G illumination. Further, the 3D lattice structures showed no significant loss in performance due to a change in the angle of illumination, whereas the performance of the flat glass substrate was significantly affected. This work opens a new paradigm for more effective capture of solar radiation that will increase the solar to energy conversion efficiency. Ministry of Education (MOE) National Research Foundation (NRF) Published version This work was supported by the Singapore Ministry of Education (MOE) Tier 2 grant (MOE T2EP50120-00081) and Tier 1 grant (2020-T1-001-147 (RG64/20)). This research was also supported by the National Research Foundation, Prime Minister’s Office, Singapore under its Campus of Research Excellence and Technological Enterprise (CREATE) programme

International audience; During the past decade, decreasing the attrition rate of drug development candidates reaching the market has become one of the major challenges in pharmaceutical research and drug development (R&D). To facilitate the decision-making process, and to increase the probability of rapidly finding and developing high-quality compounds, a variety of multiparametric guidelines, also known as rules and ligand efficiency (LE) metrics, have been developed. However, what are the ‘best’ descriptors and how far can we simplify these drug-likeness prediction tools in terms of the numerous, complex properties that they relate to?

We have developed an ab initio-based, fully quantum, numerically accurate methodology for the simulation of the exciton dynamics and time- and frequency-resolved fluorescence spectra of the cavity-controlled two-dimensional materials at finite temperatures and applied this methodology to the single-layer WSe2 system. Specifically, the multiple Davydov D2 Ansatz has been employed in combination with the method of thermofield dynamics for the finite-temperature extension of accurate time-dependent variation. This allowed us to establish dynamical and spectroscopic signatures of the polaronic and polaritonic effects as well as uncover their characteristic time scales in the relevant range of temperatures. Our study reveals the pivotal role of multidimensional conical intersections in controlling the many-body dynamics of highly intertwined excitonic, phononic, and photonic modes. Ministry of Education (MOE) Submitted/Accepted version The authors gratefully acknowledge the support of the Singapore Ministry of Education Academic Research Fund (Grant Nos. RG190/18 and RG87/20). K. Sun would also like to thank the Natural Science Foundation of Zhejiang Province (Grant No. LY18A040005) for partial Support. M. F. G. acknowledges the support of Hangzhou Dianzi University through startup funding.

Membrane-enveloped viruses are responsible for most viral pandemics in history, and more effort is needed to advance broadly applicable countermeasures to mitigate the impact of future outbreaks. In this Perspective, we discuss how biosensing techniques associated with lipid model membrane platforms are contributing to improving our mechanistic knowledge of membrane fusion and destabilization that is closely linked to viral entry as well as vaccine and antiviral drug development. A key benefit of these platforms is the simplicity of interpreting the results which can be complemented by other techniques to decipher more complicated biological observations and evaluate the biophysical functionalities that can be correlated to biological activities. Then, we introduce exciting application examples of membrane-targeting antivirals that have been refined over time and will continue to improve based on biophysical insights. Two ways to abrogate the function of viral membranes are introduced here: (1) selective disruption of the viral membrane structure and (2) alteration of the membrane component. While both methods are suitable for broadly useful antivirals, the latter also has the potential to produce an inactivated vaccine. Collectively, we emphasize how biosensing tools based on membrane interfacial science can provide valuable information that could be translated into biomedicines and improve their selectivity and performance. Ministry of Education (MOE) This work was supported by the Ministry of Education (MOE) in Singapore under grant RG111/20 and by a sponsored research agreement from LUCA AICell Inc. (RCA-LUCA AICell REQ0239282).

Cholesterol plays a critical role in modulating the lipid membrane properties of biological and biomimetic systems and recent attention has focused on its role in the functions of sub-100 nm lipid vesicles and lipid nanoparticles. These functions often rely on multivalent ligand-receptor interactions involving membrane attachment and dynamic shape transformations while the extent to which cholesterol can influence such interaction processes is largely unknown. To address this question, herein, we investigated the attachment of sub-100 nm lipid vesicles containing varying cholesterol fractions (0-45 mol %) to membrane-mimicking supported lipid bilayer (SLB) platforms. Biotinylated lipids and streptavidin proteins were used as model ligands and receptors, respectively, while the localized surface plasmon resonance sensing technique was employed to track vesicle attachment kinetics in combination with analytical modeling of vesicle shape changes. Across various conditions mimicking low and high multivalency, our findings revealed that cholesterol-containing vesicles could bind to receptor-functionalized membranes but underwent appreciably less multivalency-induced shape deformation than vesicles without cholesterol, which can be explained by a cholesterol-mediated increase in membrane bending rigidity. Interestingly, the extent of vesicle deformation that occurred in response to increasingly strong multivalent interactions was less pronounced for vesicles with greater cholesterol fraction. The latter trend was rationalized by taking into account the strong dependence of the membrane bending energy on the area of the vesicle-SLB contact region and such insights can aid the engineering of membrane-enveloped nanoparticles with tailored biophysical properties. This work was supported by the National Research Foundation of Korea (NRF) grants funded by the Korean government (MSIT; Nos. 2020R1C1C1004385 and 2021R1A4A1032782), the International Research & Development Program of the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2020K1A3A1A39112724), and a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (Grant Number: HI19C1328). This work was also partially supported by the SKKU Global Research Platform Research Fund, Sungkyunkwan University, 2022.

As a hallmark of skin aging, senescent human dermal fibroblasts (HDFs) are known to lose the ability to divide. However, they can still interact with their cellular environment and the surrounding matrix. As the skin ages, the progressive slowing down of HDFs function decreases the skin's structural integrity, which is more serious than if there is the dermal collagen matrix eroded. This leads to matters of the unbalanced barrier under the skin, skin fragility, inadequate wound healing, as well as other cosmetic issues. It is also well documented that skin aging comes with significant stiffness increases. Therefore, understanding the interactions between HDFs and the surrounding microenvironments during senescence may provide insights into skin aging. Here we aim to investigate matrix stiffness' effect on HDF senescence and elucidate possible mechanisms that make HDFs senescent. In our experiments, HDFs were cultivated on Polydimethylsiloxane (PDMS) with various stiffnesses and exposed to UV light to trigger senescence. Results show that HDFs are significantly affected by senescence when cultured on a matrix with stiffness. However, the cells are not significantly affected when cultured on a low stiffness matrix. The following characterization revealed cells cultured on stiff substrates under UV exposure had stimulated the nucleus factor kappa-B (NF-κB) activation. In contrast, cells on a matrix of softness only displayed low activation of NF-κB. NF-κB activity suppression with ammonium pyrrolidine dithiocarbamate (PDTC) decreases UV-induced HDFs senescence on stiff substrates. Taken together, we demonstrated that soft matrix defends HDFs against ultraviolet-induced senescence by inhibiting the activation of NF-κB. Nanyang Technological University The authors acknowledged the financial support from Nanyang Technological University, Singapore for PhD scholarship and funding; Zhejiang Provincial Natural Science Foundation (LY20C070010), and start-up funding from Wenzhou Institute, University of Chinese Academy of Sciences (WIUCASQD2019002).

Interphase structure characters such as single-layer interfacial thickness or number of multilayers may have a great influence on mechanical properties of continuous fibers reinforced ceramic matrix composites (CFRCMCs). However, the determination of the optimal interphase is still unclear for the complex microstructures of CFRCMCs. In this study, a novel Finite Element Method (FEM) -based numerical method considering mean scalar stiffness degradation and mean damage dissipation energy are proposed to quantitatively assess the effect of above structure characters on in-situ toughness of interphase. The proposed method has successfully applied on single pyrolytic carbon (PyC) layer and alternating silicon carbide/pyrolytic carbon (SiC-PyC) n multilayer systems. The results suggest that thicker PyC interphase will prone cause brittle fracture with lower toughness, whilst more layers with the same total thickness will improve fracture toughness for (SiC-PyC) n system. On the contrary, more layers with the same sublayer thickness will decrease in situ apparent fracture toughness. The proposed method explains well the previous contradictory experimental observations.

We investigate dynamic signatures of the singlet fission (SF) process triggered by the excitation of a molecular system to an upper singlet state SN (N > 1) and develop a computational methodology for the simulation of nonlinear spectroscopic signals revealing the SN → TT1 SF in real time. We demonstrate that SF can proceed directly from the upper state SN, bypassing the lowest excited state, S1. We determine the main SN → TT1 reaction pathways and show by computer simulation and spectroscopic measurements that the SN-initiated SF can be faster and more efficient than the traditionally studied S1 → TT1 SF. We claim that the SN → TT1 SF offers novel promising opportunities for engineering SF systems and enhancing SF yields. Ministry of Education (MOE) Submitted/Accepted version L.C. was supported by the Key Research Project of Zhejiang Lab (2021PE0AC02). L.M. was supported by the National Natural Science Foundation of China (Grant 11874125). Y.Z. gratefully acknowledges the support of the Singapore Ministry of Education Academic Research Fund (Grants RG190/18 and RG87/20). G.G.G.’s research was funded by a DUT startup grant and by the National Natural Science Foundation of China (Grant 22088102). W.N. and M.F.G. acknowledge support of Hangzhou Dianzi University through startup funding

Ion valency has strong effects on the conformation of polyelectrolyte brushes, which is important for designing the adhesive and lubrication properties of the surface. But a unified theory applicable to both monovalent and multivalent ions is still lacking. Using a consistent description of ion adsorption, we demonstrate the significant effect of ion valency on the brush conformation and the distribution of ions in the system. Our theoretical predictions are consistent with experimental and simulation results. When the system involves only monovalent ions in the solution, our theory predicts that the brush height vs. the added salt concentration undergoes the osmotic and salted brush regimes, consistent with the previous studies. Interestingly, when multivalent ions are present in the solution, the brush height undergoes an adsorption regime — which has not been reported before—in addition to the osmotic and salted regimes. Furthermore, at low salt concentrations, the ion valency of added ions can cause a phase transition in the brush. Our study provides a unified theory for the effects of ions on polyelectrolyte brushes. It reveals that the collapse behavior of the multivalent cation system is mainly caused by adsorption, which originates from the strong electrostatic interaction between monomers and multivalent cations under specific adsorption configurations. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) Submitted/Accepted version M.L. and J.Y. thank the Singapore National Research Fellowship (NRF-NRFF11-2019-0004). B.Z. acknowledges support by A*STAR under its AME YIRG Grant (Project No. A20E6c0100). M.L. thanks members of M. Muthukumar’s group (University of Massachusetts Amherst) for helpful discussions.

Electrochemical CO2 conversion is a promising way for sustainable chemical fuel production, yet the conversion efficiency is strongly limited by the sluggish kinetics and complex reaction pathways. Here we report the ultrathin conjugated metalloporphyrin covalent organic framework epitaxially grown on graphene as a two-dimensional van der Waals heterostructure to catalyze CO2 reduction. Operando X-ray absorption and density functional theory calculations reveal the strong interlayer coupling leads to electron-deficient metal centers and speeds up electrocatalysis. The Co(III)-N4 centers exhibit a CO Faradaic efficiency of 97% at a partial current density of 8.2 mA cm-2 in an H-cell, along with a stable running over 30 h. The selectivity of CO approached 99% with a partial current density of 191 mA cm-2 in a liquid flow cell, and the turnover frequency achieved 50 400 h-1 at -1.15 V vs RHE, outperforming most reported organometallic frameworks. This work highlights the key role of strong electronic coupling between van der Waals layers for accelerating the dynamics of CO2 conversion. This work is funded by the Natural Science Foundation of China (Grants 21872039 and 22072030), Science and Technology Commission of Shanghai Municipality (Grants 18JC1411700, 19DZ2270100, and 22520711100), and the Fundamental Research Funds for the Central Universities (20720220008).

A way to benefit from the favorable attributes of both organic microencapsulation, including the hermetic sealing of the organic PCM core, and inorganic microencapsulation, including dispersibility in aqueous and polar solvents and improved thermal conductivity, is outlined. The approach is demonstrated by uniformly coating organic polymer encapsulated PCMs with zinc oxide, which allows thermal percolation through the interconnected inorganic shells. We demonstrate that hydrogen peroxide sol-gel processing can be used to form such uniform zinc peroxide coatings which are then converted by chemical treatment to zinc oxide shells. The way to overcome different challenges associated with the synthesis of thin film coatings of organic PCMs by zinc oxide are addressed, and the favorable attributes of the new doubly coated PCM capsules are demonstrated. National Research Foundation (NRF) Accepted version This research is supported by a grant from the National Research Foundation, Prime Minister Office, Singapore under its Campus of Research Excellence and Technological Enterprise (CREATE) programme. The financial support of the Ministry of Science is thankfully acknowledged. We thank the Harvey M. Krueger Family Centre for Nanoscience and Nanotechnology of the Hebrew University of Jerusalem and the Israel Science Foundation. The zinc peroxide deposition was supported by the Russian Science Foundation (№17-73-10482). CHNS-analysis was performed at the User Facilities Center of IGIC RAS within the State Assignment on Fundamental Research to the Kurnakov Institute of General and Inorganic Chemistry.

Application of Ultrafast High-temperature Sintering (UHS) technique to rapidly densify barium titanate ceramics has been explored for the first time. Bulk ceramic with ~94% density was obtained by UHS at ~1340 °C for 60 seconds. The densification process was accompanied with progressive sample discolouration from light to dark grey. Further analysis indicates that oxygen vacancy and its associated Ti-rich phase Ba4Ti12O27 are present in the ceramics. Their roles in ultrafast densification and sample discoloration are discussed. Due to the presence of oxygen vacancies, the UHSed ceramics generally exhibit a colossal dielectric constant of ~ 15–30k at 1 kHz, with dielectric loss of ~0.07–0.10, while the ceramics without oxygen vacancy retain a dielectric constant of ~3000–6000 and dielectric loss of ~ 0.06 at 1 kHz which are comparable to that of the conventionally sintered ceramics. Furthermore, the challenges in applying UHS to sinter thick BT ceramics are discussed, aided by thermal simulations. The authors would like to acknowledge with thanks the financial support of the work by the project with PA number of DSOCL 21115 and the project with reference number of TLIG21–01.

Superlattices-a periodic stacking of two-dimensional layers of two or more materials-provide a versatile scheme for engineering materials with tailored properties1,2. Here we report an intrinsic heterodimensional superlattice consisting of alternating layers of two-dimensional vanadium disulfide (VS2) and a one-dimensional vanadium sulfide (VS) chain array, deposited directly by chemical vapour deposition. This unique superlattice features an unconventional 1T stacking with a monoclinic unit cell of VS2/VS layers identified by scanning transmission electron microscopy. An unexpected Hall effect, persisting up to 380 kelvin, is observed when the magnetic field is in-plane, a condition under which the Hall effect usually vanishes. The observation of this effect is supported by theoretical calculations, and can be attributed to an unconventional anomalous Hall effect owing to an out-of-plane Berry curvature induced by an in-plane magnetic field, which is related to the one-dimensional VS chain. Our work expands the conventional understanding of superlattices and will stimulate the synthesis of more extraordinary superstructures. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version The work was supported by: the National Key R&D Program of China (grant number 2020YFA0308800), the NSF of China (grant numbers 12074009, 11774009, 62174013, 12061131102 and 11734003), BIT (number 2021CX11013) and the National Key R&D Program of China (2017YFA0206301); the National Research Foundation, Singapore, under its Competitive Research Programme (NRF-CRP22-2019-0007 and NRF-CRP22-2019-0004), under its NRF-ISF joint research programme (NRF2020-NRF-ISF004-3520); and the Ministry of Education, Singapore, under its AcRF Tier 3 Programme ‘Geometrical Quantum Materials’ (MOE2018-T3-1-002). H.D., and W.G. acknowledge funding from the National Key Basic Research Program of China (2017YFB0701603) and NSFC (number 51971037). We thank X. Dai and H. M. Weng for discussions and their preliminary attempts on ab initio calculations. Y.-C.L. and K.S. acknowledge the JSPS-KAKENHI (JP16H06333 and JP22H05478), (18K14119), the JST-CREST programme (JPMJCR20B1, JMJCR20B5 and JPMJCR1993), the JSPS A3 Foresight Program, and the Kazato Research Encouragement Prize. Y.G. acknowledges funding from the Innovation Program of Shanghai Municipal Education Commission (number 2019-01-07-00- 09-E00020), Shanghai Municipal Science and Technology Commission (18JC1412800). Jianhui Zhou was supported by the High Magnetic Field Laboratory of Anhui Province. Yugui Yao acknowledges the Strategic Priority Research Program of Chinese Academy of Sciences (grant number XDB30000000).

Organic electrochemical transistors (OECTs) have recently attracted attention due to their high transconductance and low operating voltage, which makes them ideal for a wide range of biosensing applications. Poly-3,4-ethylenedioxythiophene:poly-4-styrenesulfonate (PEDOT:PSS) is a typical material used as the active channel layer in OECTs. Pristine PEDOT:PSS has poor electrical conductivity and additives are typically introduced to improve its conductivity and OECT performance. However, these additives are mostly either toxic or not proved to be biocompatible. Herein, a biocompatible ionic liquid [MTEOA][MeOSO3] is demonstrated to be an effective additive to enhance the performance of PEDOT:PSS based OECTs. The influence of [MTEOA][MeOSO3] on the conductivity, morphology and the redox process of PEDOT:PSS are investigated. The PEDOT:PSS/[MTEOA][MeOSO3] based OECT exhibits high transconductance (22.3 ± 4.5 mS μm-1), high μC* (the product of mobility μ and volumetric capacitance C*) (283.80 ± 29.66 F cm-1 V-1 s-1), fast response time (~40.57 μs) and excellent switching cyclical stability. Next, the integration of sodium (Na+) and potassium (K+) ion-selective membranes with the OECTs is demonstrated, enabling selective ions detection in the physiological range. In addition, flexible OECTs are designed for electrophysiological (ECG) signals acquisition. These OECTs have shown robust performance against physical deformation and successfully recorded high quality ECG signals. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Submitted/Accepted version W.L.L. would like to acknowledge funding support from Ministry of Education (MOE) under AcRF Tier 2 Grant (MOE2019-T2-2-106) and National Robotics Programme (W1925d0106). We would like to acknowledge the Facility for Analysis, Characterization, Testing and Simulation (FACTS) and the School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, for use of their GIWAXS, XPS and AFM facilities.

The reaction kinetics of spin-polarized oxygen evolution reaction (OER) can be enhanced by ferromagnetic (FM) catalysts under an external magnetic field. However, applying a magnetic field necessitates additional energy consumption and creates design difficulties for OER. Herein, we demonstrate that a single-domain FM catalyst without external magnetic fields exhibits a similar OER increment to its magnetized multi-domain one. The evidence is given by comparing the pH-dependent increment of OER on multi- and single-domain FM catalysts with or without a magnetic field. The intrinsic activity of a single-domain catalyst is higher than that of a multi-domain counterpart. The latter can be promoted to approach the former by the magnetization effect. Reducing the FM catalyst size into the single-domain region, the spin-polarized OER performance can be achieved without a magnetic field, illustrating an external magnetic field is not a requirement to reap the benefits of magnetic catalysts. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version This work is supported by the Singapore MOE Tier 2 grant (MOE-T2EP10220-0001) and the Singapore National Research Foundation under its Campus for Research Excellence and Technological Enterprise (CREATE) programme.

International audience; Face-centered cubic/body centered cubic (FCC/BCC) nanolaminates prepared by Accumulative Roll Bonding (ARB) have been extensively studied because of their unique mechanical properties. Recently, micro-beam bending experiments, performed on Cu/Nb ARB samples, have shown an anisotropic interface sliding behavior linked to the strong in-plane texture. To test interface sliding on a macroscale we have developed a shear test based upon a specific sample geometry and on in situ tensile loading on an X-ray synchrotron beamline. As received nanolaminate samples exhibit a very anisotropic crystallographic texture as expected from the fabrication process. In situ X-ray diffraction in the sheared zone during mechanical loading yields strains in Cu and Nb. Early brittle failure prevents investigating further the sliding at interfaces. This is probably caused by crack initiation from the inner surfaces of the notches used to induce shear.

In recent years, using an external magnetic field to promote the oxygen evolution reaction (OER) on magnetic catalysts has attracted great attention. It is an appealing topic, but with a puzzle where the increment comes from. The early theoretical work has predicted that the production of triplet dioxygen in OER can be facilitated by the spin-polarization effect in a single domain of magnetic catalysts. Recent progress has revealed that the M-O radical species is the key for promoting the triplet dioxygen formation, which is evident by the pH-dependent enhancement by magnetization. However, magnetization of a ferromagnetic material only changes its magnetic domain structure in the case of bulk ferromagnetic catalytic structures. It does not directly change the spin orientation of unpaired electrons in the material. Thus, where would be the OER enhancement coming from? The confusion further lies in that each magnetic domain is a small magnet and theoretically the spin-polarization promoted OER already occurs on these magnetic domains, and thus the enhancement should have been achieved without magnetization. Here, we demonstrate that the enhancement comes from the disappeared domain wall between magnetic domains. The proportion of domain wall occupied surface before magnetization determines the degree of enhanced OER by magnetization. Due to the spin-facilitated promotion effect, the OER on surface occupied by magnetic domains are more favourable than that on surface occupied by domain walls. Magnetization leads to the evolution of the magnetic domain structure, from a multi-domain one to a single domain one, in which the domain wall disappears. Consequently, the occupied by the domain wall is reformatted into one by a single domain, on which the OER follows the spin-facilitated pathways and thus the overall increment on the electrode occurs. This study fills the missing gap for understanding the magnetic field enhanced OER and it further explains the type of ferromagnetic catalysts which can give increment by magnetization.