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Toluene is one of the simplest mono-substituted benzene derivatives and an important precursor to form polycyclic aromatic hydrocarbons (PAHs) and soot. However, there is a lack of critical understanding of the formation mechanisms of the toluene molecule. In this work, we explore hightemperature reactions of propargyl radical addition to 1,3-butadiene in a tubular flow microreactor. We obtain experimental evidence for the distinct formations of three C7H8 isomers consisting of toluene, 1,3,5-cycloheptatriene, and 5-methylene-1,3-cyclohexadiene discriminated by synchrotron VUV photoionization efficiency curves. Toluene is identified as the dominant product, which shows strong contrast with the calculated results of the system. By performing theoretical calculations and kinetic simulations, we found that 5-methylene-1,3-cyclohexadiene is a key product of the primary reaction, and toluene formation is enhanced by unavoidable secondary reactions, such as unimolecular isomerization and/or H-assisted isomerization reactions in the SiC microreactor. The current work provides competitive pathways for the enhanced formation of toluene, and may further help disentangle the toluene-promoted molecular growth mechanism of PAHs in combustion environments. [ABSTRACT FROM AUTHOR]

Electromechanical coupling plays a key role in determining the performance of stretchable strain sensor. Current regulation of the electromechanical coupling in stretchable strain sensor is largely restricted by the intrinsic mechanical properties of the device. In this study, a microfluidic strain sensor based on the core–shell package design with the auxetic metamaterial (AM) is presented. By overriding the mechanical properties of the device, the AM in the package effectively tunes the deformation of the microfluidic channel with the applied strain and configures the directional strain sensitivity with a large modulation range. The gauge factor (GF) of the strain sensor in the radial direction of the channel can be gradually shifted from the intrinsically negative value to a positive one by adopting the AMs with different designs. By simply replacing the AM in the package, the microfluidic strain sensor with the core–shell package can be configurated as an omnidirectional or directional stretchable strain sensor. With the directional sensitivity brought by the rational AM design, the application of the AMintegrated strain sensor in the skin-mounted tactile detection is demonstrated with high tolerance to unintended wrist movements. [ABSTRACT FROM AUTHOR]

Six new hybrid compounds based on polyoxometalates and transition metal complexes, [SiW12O40][Ag4(2,2'-bpy)4(4,4'-bpy)3]·2H2O (1), [SiMo12O40][Cu(2,2'-bpy)(H4,4'-bpy)2(H2O)][H4,4-bpy] (2), [PMo12V2O42][Cd2(Phen)2(4,4'-bpy)2(H2O)2(C2O4)]·2H2O (3), [PMo12V2O42][Cu2(4,4'-bpy)2][Cu2(Phen)(4,4'-bpy)2]·3H2O (4), [SiMo12V2O42][Cu2(Phen)2(4,4'-bpy)]2 (5) and [GeMo12V2O42][Cu2(Phen)2(4,4'-bpy)]2 (6) (bpy = bipyridine, Phen = phenanthroline), have been synthesized and characterized. Compound 1 contains a discrete tetranuclear silver-2,2'-bpy-4,4'-bpy complex; compound 2 is the first example where the polyoxometalate supports a metal-aqua-2,2'-bpy-4,4'-bpy complex; it should be noted that the complex contains a 2,2'-bpy and two 4,4'-bpy ligands; compound 3 is the first hybrid compound based on polyoxometalates and metal- aqua-4,4'-bpy-oxalic-phenanthroline complexes; and compound 4 is a novel hybrid compound based on polyoxometalates, extended metal-4,4'-bpy complexes and extended metal-4,4'-bpy-phenanthroline complexes together. Compounds 5 and 6 are isomorphous and isostructural; both exhibit a supramolecular structure constructed from bicapped Keggin POMs and metal-4,4'-bpy-phenanthroline complexes. [ABSTRACT FROM AUTHOR]

Novel low-molecular-weight organogelators (LMOGs) 1and 2derived from glycine-glutamic-acids (GGA) based dipeptide were synthesized. The difference on the chemical structures between 1and 2resulted in some interesting variations on their gelling behavior and fluoride anion (F−) responsive properties. Gelator 1could gel aromatic solvents effectively, while gelator 2possessed excellent gelation ability in protic solvents. Upon the addition of 0.5 equiv. F−, the toluene gel of 1transformed into solution due to the disruption of the intermolecular hydrogen-bonding, whereas the alcohol gel of 2was stable and preserved even by introducing 20 equiv. F−. Interestingly, 2could be regarded as an efficient receptor for F−in acetonitrile (MeCN) solution. After the addition of F−, the fluorescent emission band of 2red-shifted from 360 to 420 nm with the emission intensity enhanced drastically; the intensity of the CD signal decreased and almost disappeared after addition of 2 equiv. F−. These changes were due to the conformational change and hydrogen-bonding interaction between urea groups and F−. The results indicated that GGA-based 1and 2might represent potential sensor materials for the naked-eye detection of F−. [ABSTRACT FROM AUTHOR]

Silicon is a promising alternative to current thermoelectric materials (Bi2Te3). Silicon nanoparticle based materials show especially low thermal conductivities due to their high number of interfaces, which increases the observed phonon scattering. The major obstacle with these materials is maintaining high electrical conductivity. Surface functionalization with phenylacetylene shows an electrical conductivity of 18.1 S m−1 and Seebeck coefficient of 3228.8 μV K−1 as well as maintaining a thermal conductivity of 0.1 W K−1 m−1. This gives a ZT of 0.6 at 300 K which is significant for a bulk silicon based material and is similar to that of other thermoelectric materials such as Mg2Si, PbTe and SiGe alloys. [ABSTRACT FROM AUTHOR]

Three novel supramolecular compounds [PWVI10.5WV1.5O40][Cu(2, 2′-bpy)2]4.5(1), [CuI(Phen)2]4[CuI5Cl4(Phen)4][PWVI10WV2O40]2·4H2O(2) and [CuI(Phen)2]4[CuI5Cl4(Phen)4][BWVI12O40]2·2H2O(3) (bpy = bipyridine, Phen = 1,10-Phenanthroline) have been synthesized and characterized by IR, UV-Vis, TG, XRD, elemental analyses and single crystal X-ray diffraction analyses. Compound 1is the first example of a hybrid compound which is constructed from polyoxometalates and supramolecular noncovalent coordination cages. Both compounds 2and 3are constructed from two different types of building blocks: polyoxometalates and metal halide fragments. [ABSTRACT FROM AUTHOR]

Five novel heteropolyanions have been synthesized and characterized by IR, UV-vis, XPS spectroscopy, XRD, and elemental analyses. Single-crystal X-ray diffraction analyses reveal that these five compounds represent novel examples of compounds based on the combination of polyoxometalates, transition metal coordination complexes and organic amines. Of which 1, 2and 3exhibit 0D structures of polyoxometalate supported transition metal coordination complexes, while 4and 5exhibit novel 1D structures constructed from polyoxometalates and transition metal coordination complexes. [ABSTRACT FROM AUTHOR]

Two new compounds based on AsIII–VIVpolyoxometalates, [HAs6V15O42(H2O)][Cu(enMe)2]2.5·2H2O (1), [H2enMe]2[As8V14O42(H2O)]·3H2O (2), have been hydrothermally synthesized and characterized by IR, UV-vis, ESR, XPS spectra, elemental analyses, magnetic susceptibility studies and single-crystal X-ray diffraction analyses, respectively. X-Ray crystallographic studies reveal that 1represents the first example of 2D structure constructed from [HAs6V15O42(H2O)]5−anions and transition metal coordination complexes, in addition, it exhibits the first brick-wall-like 2D layer structure constructed from polyoxometalates and transition metal coordination complexes. 2exhibits a very interesting stacking mode. The study of magnetic susceptibilities demonstrates the presence of antiferromagnetic interactions in both 1and 2. [ABSTRACT FROM AUTHOR]

The article focuses on the latest issue of the Journal of Materials Chemistry A, highlighting reviews on enhancing supercapacitor electrode performance with electrospun carbon nanofibers and developing polymer-based films for self-charging power systems.

To promote the development of anode materials for rechargeable batteries, we investigated the relationships between the structure characteristics and the electronic, mechanical, adsorption, diffusion and electrochemical properties of the designed Ti3N2T2/VS2 (T = F, O, OH) heterostructures for lithium/sodium/magnesium-ion batteries using density functional theory calculations. Three optimal heterostructures with different terminations, Ti3N2F2/VS2, Ti3N2O2/VS2 and Ti3N2(OH)2/VS2, were selected, and the mechanisms of charge transfer and ion diffusion were expounded clearly. These heterostructures can be used as novel anode materials based on excellent thermal stability, metallicity, mechanical stability, adsorption and diffusion performance. The results indicate that the main contributors to the metallicity are the d-orbital electronic states derived from Ti and V. The intrinsic nature of metallicity guarantees a good electrical conductivity that enables rapid charge migration and accelerates the redox process. The ion insertion not only affects the density of states distributions of the heterostructures, but also enhances their Fermi levels. The amount of charge transfer from a metal ion to VS2 is more than that to Ti3N2T2 at the respective interlayers of Ti3N2F2/VS2 and Ti3N2(OH)2/VS2, while the opposite trend appears for Ti3N2O2/VS2. The monolayer that gains more charges from the ion corresponds to the charge acceptor in the pristine heterostructure without ion adsorption. The most favorable ion-diffusion path between two optimal adsorption sites inevitably passes through the second optimal adsorption site with the second smallest adsorption energy. Considering the structural integrity, strong adsorption abilities, low diffusion energy barriers, high capacities and suitable open-circuit voltages, Ti3N2F2/VS2 and Ti3N2(OH)2/VS2 are proposed to be promising high-performance anode materials for SIBs and LIBs/MIBs, respectively, and Ti3N2O2/VS2 is an ideal anode material for LIBs/SIBs/MIBs. [ABSTRACT FROM AUTHOR]

The document is a contents list for the Journal of Materials Chemistry A, featuring articles and reviews on various topics such as energy and sustainability, sodium storage, pressure sensors, and green nanogenerators. The journal aims to support the chemistry community by reinvesting its profits. The papers cover a wide range of subjects, including passive cooling, solar-powered ammonia production, formaldehyde degradation, and oil spill removal, among others. Each paper offers unique insights and findings in their respective fields. [Extracted from the article]

Due to the high ionic conductivity and low cost, Li1.3Al0.3Ti1.7(PO4)3 (LATP) has emerged as a promising solid-state electrolyte for next-generation Li metal solid-state batteries. However, the susceptibility of LATP to side reactions with Li metal and the significant resistance at grain boundaries pose major challenges for the applications of all-solid-state batteries. In this work, the non-equilibrium microstructure at the interface of a LATP composite solid electrolyte (84 wt% LATP and 16 wt% LiTFSI) was adjusted by two-step cold sintering, reducing interfacial transport barriers for optimizing ionic transport paths and reducing sensitivity to Li metal anodes, thus increasing the ionic conductivity and interfacial stability of solid electrolytes. While preserving the original grain structure, the grain boundary resistance was significantly reduced, resulting in an impressive ionic conductivity of 7.3 × 10−4 S cm−1. Additionally, the solid electrolyte had a high density of 97% and demonstrated excellent interfacial compatibility and electrochemical stability by maintaining stable cycling for 2300 h at 0.1 mA h cm−2. This further demonstrates the favorable effect of the non-equilibrium microstructure on ion transport across grain boundaries and enhancing interfacial stability, which is crucial for achieving high performance. In conclusion, two-step cold sintering, with its unique process, offers significant advantages in modulating the interfacial microstructure and presents a novel solution for interfacial engineering. [ABSTRACT FROM AUTHOR]

As a typical layered oxide material, Li2TiO3 has attracted considerable attention in the energy revolution and military industries, owing to its lithium-rich and "zero-strain" characteristics. However, its phase-transition behavior under high pressure remains unclear. Herein, we report a second-order phase transition from the monoclinic phase to a higher-symmetry phase in nano-polycrystalline Li2TiO3 at 43 GPa by in situ high-pressure Raman experiments and first-principles calculations at 300 K. As validated by the experiments and calculations, the distortion of layered oxide-TiO6 in Li2TiO3 is crucial in the phase transition. By modulating the gap between octahedral-TiO6 layers, we propose a potential Li2TiO3 structural model for improving the electrochemical performance of lithium-ion batteries. Our findings suggest that, based on its high-pressure phase, Li2TiO3 is a promising candidate for layered cathode materials and solid tritium breeding materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The maintenance and incremental growth of the alveolar bone at the tooth extraction site, to achieve the required height and width for implant restoration, remains a major clinical challenge. Here, the concept of restoring the electrical microenvironment to improve the effects of alveolar ridge preservation (ARP) was investigated in a mini-pig preclinical model. The endogeneous electrical microenvironment of the dental alveolar socket was recapitulated by fabricating a biomimetic ferroelectric BaTiO3/poly(vinylidene fluoridetrifluoroethylene) (BTO/P(VDF-TrFE)) non-resorbable nanocomposite membrane polarized by corona poling. The polarized nanocomposite membrane exhibited excellent electrical stability. After implantation with bone grafts and covering with the charged membrane in tooth extraction sites for three months, both the vertical and horizontal dimension resorption of the alveolar ridge were significantly prevented, as assessed by cone beam computed tomography (CBCT) analyses. Micro-CT analysis showed that the charged membrane induced significant enhancement of newly regenerated bone at the tooth extraction sites. Histological analysis further confirmed that the restoration of the electrical microenvironment significantly promoted buccal alveolar bone regeneration and maturation. In addition, the charged membranes can maintain their structural integrity during the entire implantation period and exhibit positive long-term systemic safety, as assessed by preclinical sub-chronic systemic toxicity. These findings thus provide an innovative strategy for restoring the electrical microenvironment to enhance ARP following dentition defect and edentulism, which could further advance prosthodontics implant technology. [ABSTRACT FROM AUTHOR]

The electric-field-controlled (E-controlled) photoluminescence (PL) effect in inorganic materials has aroused great interest because of its potential applications in displays, optical communication, and data storage. However, current ferroelectric-type PL materials which show either irreversible or reversible but insufficient PL tunability encounter certain limitations. Herein, a strategy of utilizing the E-induced antiferroelectric–ferroelectric (AFE–FE) phase transition is proposed to achieve a giant and reversible modulation of the PL effect. The feasibility of the strategy is evidenced in Er3+ doped Pb0.96La0.04Zr0.9Ti0.1O3 (PLZT-Er) AFE ceramics, where an alternate E of 80 kV cm−1 can reversibly trigger an ∼30% PL enhancement. Moreover, six nonlinear change sections and two distinguishable PL states are revealed under a cycle of E. This tunability is attributed to the E-induced electric dipole flips and corresponding symmetry changes during the AFE–FE phase transition. Such in situ E-dependent PL modulation suggests a new type of optical–electric coupling mechanism that is fundamentally based on symmetry, which opens up a new approach for multifunctional optoelectronic devices. [ABSTRACT FROM AUTHOR]

The industrial-scale NH3 production still heavily depends on the Haber–Bosch process, which not only demands high energy consumption but also emits a large amount of CO2. The electrochemical fixation of N2 to NH3 under ambient conditions is regarded as an eco-friendly and sustainable approach, but stable and efficient electrocatalysts are demanded for the N2 reduction reaction under ambient conditions. In this communication, ReS2 nanosheet array on carbon cloth (ReS2/CC) is first utilized in NRR. This ReS2/CC exhibits high catalytic activity and strong long-term electrochemical durability. The Faraday efficiency of ReS2/CC is 0.78% and the NH3 yield of ReS2/CC is 3.61 × 10−10 mol s−1 cm−2 at −0.4 V versus reversible hydrogen electrode in 0.1 M HCl. [ABSTRACT FROM AUTHOR]

Emerging single atom catalysts (SACs), especially carbon-based SACs are appealing materials in environmental catalysis because of their ultrahigh performances, environmental friendliness, structural/chemical robustness, and the maximum utilization of active metal sites. The metal centres, carbon matrixes, and coordination characteristics collectively determine the electronic features of carbon-based SACs, and their behaviours in catalysing peroxide activation and efficiencies in advanced oxidation processes (AOPs). However, there is lack of a comprehensive and critical review reporting the successful marriage of carbon-based SACs in AOP-based remediation technologies. It is particularly necessary to systematically compare and reveal the catalytic sites and the associated mechanisms of carbon-based SACs in diverse AOP systems. In this review, we highlight the synthetic strategies, characterisation, and computation of carbon-based SACs, and for the first time, showcase their innovative applications in AOP technologies. We unveil the origins of versatile catalytic oxidation pathways in different AOP systems and the mechanisms of micropollutant degradation over carbon-based SACs, distinguished from the upsized counterparts (metals/oxides and carbon substrates). We also provide directions to the rational design of on-demand SACs for green chemistry and environmental sustainability. Also, we suggest a designated and integrated experimental/theoretical protocol for revealing the structure-catalysis relations of SACs in AOP applications, and propose the prospects for future opportunities and challenges. [ABSTRACT FROM AUTHOR]

Email dalton-rsc@rsc.org Dalton Transactions (electronic: ISSN 1477-9234) is published 48 times a year by the Royal Society of Chemistry, Thomas Graham House, Science Park, Milton Road, Cambridge, UK CB4 0WF. Through our high impact journals and publications we connect the world with the chemical sciences and invest the profits back into the chemistry community. DaltonTransactions AninternationaljournalofinorganicchemistryincorporatingActaChemicaScandinavica rsc.li/dalton The Royal Society of Chemistry is the world's leading chemistry community. [Extracted from the article]

The Eu-doped K0.5Na0.5NbO3 pellucid ceramics were first prepared via a conventional solid-state reaction, and they exhibited light illumination-induced high-contrast photochromism of both optical transmittance and photoluminescence behaviors. Through thermal treatment, the optical performances could return to their initial states and displayed excellent reversibility. Eu3+ ions were selected as the luminescent activator for detecting the local environment of the K0.5Na0.5NbO3 host. Meanwhile, the effects of the amount of Eu3+ present on phase structures, microstructures, optical transmittance and photoluminescence intensities were systematically investigated. The results suggest that Eu-doped K0.5Na0.5NbO3 transparent ceramics possess multifunctionality including photochromism, photoluminescence and optical switching properties, and that they exhibit promising potential for non-destructive optical data storage application. [ABSTRACT FROM AUTHOR]

Superconducting devices such as superconducting quantum interference devices, superconductor nanowire single photon detectors, and superconducting quantum chips have unique performances not available in conventional semiconductor devices. However, most of the superconducting devices are fabricated on rigid substrates consequently limiting applications requiring mechanical flexibility. Herein, wafer-scale flexible superconducting devices are designed and constructed based on a two-dimensional (2D) superconducting system consisting of superconducting discrete Pb nano-islands and single-crystalline graphene on a stretchable parylene C substrate. Owing to the perfect two-dimensional electron gas (2DEG) provided by single-crystalline graphene, the discrete Pb nano-islands are coupled to form a global zero-resistance superconducting state in the hybrid system. Since the discrete island structure is integrated with flexible graphene and parylene C, the superconducting device works steadily even in the bent state. In addition, the Berezinskii–Kosterlitz–Thouless (BKT) type phase transition, the hallmark of two-dimensional superconductivity, can be tuned by the back-gate bias. Our results suggest a convenient and effective strategy to design and prepare large-scale and flexible superconducting systems. [ABSTRACT FROM AUTHOR]

A highly porous ternary TiO2/Co3O4/Ni photocatalyst is successfully constructed from a hetero-metal organic framework (H-MOF) template and via a facile photoreduction method. The photocatalytic H2 production coupled with the formation of H2O2 on TiO2 is improved by co-loading an oxidation promoter (Co3O4) and a reduction promoter (Ni) owing to the following factors: porous Co3O4 promotes the optical-response ability and surface water oxidation kinetics of TiO2, and in situ photo-deposited Ni facilitates the transport and utilization efficiency of photo-excited electrons. Owing to the synergy of the improved specific surface area and improved separation as well as utilization of photogenerated charge carriers, the optimal ternary TiO2/5at%Co3O4/0.5at%Ni heterostructure exhibits a hydrogen production activity 8.7 times higher than that of pure TiO2, and demonstrates obvious photocatalytic hydrogen evolution even in pure water, with stoichiometric H2O2 production. This work will provide insights into the design and synthesis of noble metal-free dual cocatalyst systems for efficient charge separation and transfer. [ABSTRACT FROM AUTHOR]

Formaldehyde is an essential building block for hundreds of chemicals and a promising liquid organic hydrogen carrier (LOHC), yet its indirect energy-intensive synthesis process prohibits it from playing a more significant role. Here we report a direct CO reduction to formaldehyde (CORTF) process that utilizes hydrogen underpotential deposition to overcome the thermodynamic barrier and the scaling relationship restriction. This is the first time that this reaction has been realized under ambient conditions. Using molybdenum phosphide as a catalyst, formaldehyde was produced with nearly a 100% faradaic efficiency in aqueous KOH solution, with its formation rate being one order of magnitude higher compared with the state-of-the-art thermal catalysis approach. Simultaneous tuning of the current density and reaction temperature led to a more selective and productive formaldehyde synthesis, indicating the electrochemical and thermal duality of this reaction. DFT calculations revealed that the desorption of the *H2CO intermediate likely served as the rate-limiting step, and the participation of H2O made the reaction thermodynamically favorable. Furthermore, a full-cell reaction set-up was demonstrated with CO hydrogenation to HCHO achieved without any energy input, which fully realized the spontaneous potential of the reaction. Our study shows the feasibility of combining thermal and electrochemical approaches for realizing the thermodynamics and for scaling relationship-confined reactions, which could serve as a new strategy in future reaction design. [ABSTRACT FROM AUTHOR]

A novel Hg2+-responsive thermometer system for translating mercury detection into temperature monitoring was developed based on an aggregation-activated oxidase-like activity of gold nanoparticles. [ABSTRACT FROM AUTHOR]