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Phase change materials (PCMs) have received significant attention in various fields due to their remarkable ability to undergo phase transitions and induce substantial changes in their physical properties. One such material, vanadium dioxide (VO2), has emerged as a prominent PCM that exhibits a reversible metal–insulator transition near room temperature. These transitions are accompanied by rapid modifications in electrical conductivity and surface properties. Efforts have been made recently to enhance the performance and expand the utility of VO2 by combining it with other materials and structures. One effective approach is the use of plasmonic hybridization with vanadium dioxide (VO2), which enhances the optical and functional properties of VO2-based materials. This study offers a comprehensive review of previous research, with a specific focus on investigating the plasmonic hybridization in VO2@Au nanoshells. To analyze the plasmonic modes in this innovative core–shell structure, a combined theoretical and simulation-based approach is employed. The investigation encompasses both the semiconductor and metallic phases of the VO2 core, revealing the presence of sphere and cavity plasmonic modes. Remarkably, the results highlight that the cavity frequency becomes the dominant mode beyond wavelengths of 778 nm, particularly in the metallic phase. Furthermore, this study presents valuable insights into the charge distribution resulting from symmetric and asymmetric plasmon oscillations at specific wavelengths, particularly in the optimized scenario of the VO2@Au nanoshell. [ABSTRACT FROM AUTHOR]

In this work, we report a high-pressure study on fergusonite-type LaNbO4. Powder x-ray diffraction and Raman spectroscopic experiments support the occurrence of a phase transition between 11 and 14 GPa. The transition takes place from a monoclinic fergusonite-type structure (space group I2/a) to another monoclinic structure (space group P21/c). The phase transition is reversible, and the high-pressure phase is isomorphic to the high-pressure phase of HoNbO4. The high-pressure phase remains stable up to 33.3 GPa, the highest pressure reached in the present measurements. Density-functional theory calculations found that in the pressure range of the studies; the high-pressure phase has a higher enthalpy than the low-pressure fergusonite phase. We propose that the high-pressure phase is metastable and it is observed because of non-hydrostatic conditions in the experiments. The pressure dependence of unit-cell parameters of the low-pressure phase and the room-temperature equation of state are reported. The pressure dependence of various Raman and IR frequencies as obtained from experiment and theory is also reported. For the fergusonite phase, we have also obtained the isothermal compressibility tensor, elastics constants, and elastic moduli. [ABSTRACT FROM AUTHOR]

We extend a recently proposed kinetic theory of virus capsid assembly based on Model A kinetics and study the dynamics of the interconversion of virus capsids of different sizes triggered by a quench, that is, by sudden changes in the solution conditions. The work is inspired by in vitro experiments on functionalized coat proteins of the plant virus cowpea chlorotic mottle virus, which undergo a reversible transition between two different shell sizes (T = 1 and T = 3) upon changing the acidity and salinity of the solution. We find that the relaxation dynamics are governed by two time scales that, in almost all cases, can be identified as two distinct processes. Initially, the monomers and one of the two types of capsids respond to the quench. Subsequently, the monomer concentration remains essentially constant, and the conversion between the two capsid species completes. In the intermediate stages, a long-lived metastable steady state may present itself, where the thermodynamically less stable species predominate. We conclude that a Model A based relaxational model can reasonably describe the early and intermediate stages of the conversion experiments. However, it fails to provide a good representation of the time evolution of the state of assembly of the coat proteins in the very late stages of equilibration when one of the two species disappears from the solution. It appears that explicitly incorporating the nucleation barriers to assembly and disassembly is crucial for an accurate description of the experimental findings, at least under conditions where these barriers are sufficiently large. [ABSTRACT FROM AUTHOR]

Layered transition‐metal oxides (NaxTMO2) are one of the most promising cathode materials for sodium‐ion batteries due to their high theoretical specific capacities, good conductivity, and environmental friendliness. However, several key scientific issues of NaxTMO2 cathode materials still persist in practical applications: i) complex phase transitions during the charge/discharge process owing to the slip of the transition‐metal layer; ii) the tendency for the interface to react with the electrolyte, resulting in structure degradation, and iii) reactions between active materials and H2O as well as CO2 on exposure to air in the environment to form alkaline substances on the surface. To understand electrochemical storage mechanisms and solve these problems, several modification strategies of NaxTMO2 have been reported recently, including bulk doping, concentration gradient structure design, interface regulation, and intergrowth structure construction. This review focuses on reversible phase transitions, stable interface regulation, and multifunctional intergrowth structure of the NaxTMO2 material from the inside to the outside. The future research directions for NaxTMO2 are also analyzed, providing guidance for the development of commercial layered oxides for next‐generation energy storage systems. [ABSTRACT FROM AUTHOR]

Summary Light is essential not only for photosynthesis but also for the regulation of various physiological and developmental processes in plants. While the mechanisms by which light regulates transcription and protein stability are well established, the effects of light on RNA methylation and their subsequent impact on plant growth and development are less understood. Upon exposure to blue light, the photoreceptor cryptochromes form nuclear speckles or nuclear bodies, termed CRY photobodies. The CRY2 photobodies undergo light‐induced homo‐oligomerization and liquid–liquid phase separation (LLPS), which are crucial for their physiological activity. Recent studies have proposed that blue light‐induced CRY2 LLPS increases the local concentration or directly enhances the biochemical activities of RNA N6‐methyladenosine (m6A) methyltransferases, thus, to regulate circadian clock and maintain Chl homeostasis through processes of RNA decay or translation. This review aimed to elucidate the functions of CRY2 and LLPS in RNA methylation, focusing on the light‐controlled reversible phase transitions regulon and the outstanding questions that remain in RNA methylation. [ABSTRACT FROM AUTHOR]

Temperature‐responsive hydrogels including lower critical solution temperature (LCST)‐ and upper critical solution temperature (UCST)‐type hydrogels are attractive in various fields. However, the swift switch between LCST and UCST stimuli‐responsive behaviors remains intriguing and challenging. Here is reported a kind of hydrogel with pH‐gated LCST and UCST response behaviors. This is achieved using the hydrogen bonding between carboxylic acid groups of poly(acrylic acid‐co‐acrylamide) and hydroxyl groups of hydroxypropyl cellulose (HPC). The poly(acrylic acid‐co‐acrylamide)‐HPC (PACA‐HPC) hydrogels exhibit pH‐gated reversible LCST‐UCST phase transition behavior. When the transparent PACA‐HPC hydrogel is placed in an acid bath, the COO− groups get protonated, rapidly forming hydrogen bonds with HPC to render a light‐scattering state making the hydrogel opaque. Furthermore, the opaque hydrogel exhibits UCST phase transition behavior at 20–45 °C. When the opaque PCAC‐HPC hydrogel is placed in an alkaline environment, hydrogen‐bonded complexes gradually dissociate as the COOH groups are deprotonated to form a homogeneous transparent state. The transparent hydrogel exhibits LCST phase transition behavior at 20–45° C. Therefore, is shown the hydrogen bonding strategy to fabricate hydrogels with tunable LCST and UCST responses. With this pH‐gated hydrogel with switchable LCST/UCST responsive behaviors, are demonstrated its applications in smart windows and information encryption. [ABSTRACT FROM AUTHOR]

Inspired by the intelligent gel phase transition effect, we applied temperature-responsive γ-FeOOH/KGM(Ga)/PNIPAM hydrogel with reversible sol-gel transition for uranium enrichment and separation in carbonate-containing wastewater. In carbonate-containing wastewater, the hydrogel achieved a high uranium removal rate of 92.3%, exceeding 90% even in actual uranium mine wastewater. Additionally, the adsorption-reduction-nucleation-crystallization mechanism of uranium on the temperature-responsive hydrogel was revealed using multi-spectral coupling techniques. [Display omitted] Exploiting the intelligent photocatalysts capable of phase separation provides a promising solution to the removal of uranium, which is expected to solve the difficulty in separation and the poor selectivity of traditional photocatalysts in carbonate-containing uranium wastewater. In this paper, the γ-FeOOH/konjac glucomannan grafted with phenolic hydroxyl groups/poly- N -isopropylacrylamide (γ-FeOOH/KGM(Ga)/PNIPAM) thermosensitive hydrogel is proposed as the photocatalysts for extracting uranium from carbonate-containing uranium wastewater. The dynamic phase transformation is demonstrated to confirm the arbitrary transition of γ-FeOOH/KGM(Ga)/PNIPAM thermosensitive hydrogel from a dispersed state with a high specific surface area at low temperatures to a stable aggregated state at high temperatures. Notably, the γ-FeOOH/KGM(Ga)/PNIPAM thermosensitive hydrogel achieves a remarkably high rate of 92.3% in the removal of uranium from the wastewater containing carbonates and maintains the efficiency of uranium removal from uranium mine wastewater at over 90%. Relying on electron spin resonance and free radical capture experiment, we reveal the adsorption-reduction-nucleation-crystallization mechanism of uranium on γ-FeOOH/KGM(Ga)/PNIPAM thermosensitive hydrogel. Overall, this strategy provides a promising solution to treating uranium-contaminated wastewater, showing a massive potential in water purification. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) have gained a tremendous interest as a means to actively tune nanophotonic devices through the large optical modulation produced by their amorphous to crystalline reversible transition. Recently, materials such as Sb2S3 emerged as particularly promising low loss PCMs, with both large refractive index modulations and transparency in the visible and near‐infrared. Controlling the local and reversible phase transition in this material is of major importance for future applications, and an appealing method to do so is to exploit pulsed lasers. Yet, the physics and limits involved in the optical switching of Sb2S3 are not yet well understood. Here, the reversible laser‐induced phase transition of Sb2S3 is investigated, focusing specifically on the mechanisms that drive the optically induced amorphization, with multi‐physics considerations including the optical and thermal properties of the PCM and its environment. The laser energy threshold for reversibly changing the phase of the PCM is determined through both theoretical analysis and experimental investigation, not only between fully amorphous and crystalline states but also between partially recrystallized states. Then, the non‐negligible impact of the material's polycrystallinity and anisotropy on the power thresholds for optical switching is revealed. Finally, the challenges related to laser amorphization of thick Sb2S3 layers are addressed, as well as strategies to overcome them. These results enable a qualitative and quantitative understanding of the physics behind the optically‐induced reversible change of phase in Sb2S3 layers. [ABSTRACT FROM AUTHOR]

[Display omitted] Switchable microemulsions (MEs) are those capable of adaptively responding to the action of internal or external stimuli. For redox-switchable MEs to obtain high-efficiency phase separation and surfactant recycling, it may be one of the keys to adequately turn off the interfacial activity of surfactants and reduce the solubility of the closed surfactants in the oil phase. Monophasic MEs consisting 11-butylselanyl-undecyl sulfate sodium (C 4 SeC 11 SO 4 Na), n -butanol, n -octane, and water were fabricated using the pseudo-ternary phase diagram method. Their structural features and droplets size were characterized by conductivity, dynamic light scattering (DLS) and cryogenic transmission electron microscopy (cryo-TEM), respectively. The redox response of MEs was studied using a combination of visual observations and DLS, cryo-TEM, nuclear magnetic resonance (NMR) and thin-layer tomography. The efficient recycling of C 4 SeC 11 SO 4 Na from a well-emulsified eluent is conceptually demonstrated. The reversible transition between C 4 SeC 11 SO 4 Na and C 4 SeOC 11 SO 4 Na is achieved under the alternating action of H 2 O 2 and N 2 H 4 , by which C 4 SeC 11 SO 4 Na-based monophasic MEs are able to efficiently demulsify and regenerate, respectively, regardless of their type. After H 2 O 2 -induced demulsification of the MEs, C 4 SeOC 11 SO 4 Na can be efficiently recycled with the water phase. We hope that such a redox-switching method may benefit some technological applications. For example, it offers exciting possibilities for simultaneous recycling C 4 SeC 11 SO 4 Na and removal of oil from a well-emulsified eluent. Around 97.1 ± 0.3 % of C 4 SeC 11 SO 4 Na could be recycled over five cycles with no apparent loss. After a simple and conventional treatment with anion-exchange resin and active carbon, the total organic carbon and chemical oxygen demand of the waste water were 17.4 ± 2.8 and 26.2 ± 1.4 mg/L, respectively. [ABSTRACT FROM AUTHOR]

Monolayer MoTe2 exhibits a variety of derivative structural phases and associated intriguing electronic properties that enable a wealth of potential applications in future electronic and optoelectronic devices. However, a comprehensive study focusing on the complexities of the controllable phase evolution in this atomically thin film has yet to be performed. This work aims to address this issue by systematically investigating molecular beam epitaxial growth of monolayer Mo–Te compounds on bilayer graphene substrates. By utilizing scanning tunneling microscopy, we explored a series of thermally driven structural phase evolutions, including distinct T′-MoTe2, H-MoTe2, Mo6Te6 nanowires, and multistoichiometric MoTe2−x. Furthermore, we carefully investigated the critical effects of the growth parameters—annealing temperature and time and tellurium concentration—on the controllable and reversible phase transformation within monolayer MoTe2−x. The findings have significant implications for understanding the thin film synthesis and phase transformation engineering inherent to two-dimensional crystals, which can foster further development of high-performance devices. [ABSTRACT FROM AUTHOR]

Precise control over polarity in field‐effect transistors (FETs) plays a pivotal role in the design and construction of complementary metal–oxide–semiconductor (CMOS) logic circuits. In particular, achieving such precise polarity control in 2D semiconductors is crucial for the further development of advanced electronic applications beyond unit devices. This paper presents a systematic investigation on the reversible transition of carrier types in a 2D MoTe2 semiconductor under different annealing atmospheres. Photoemission spectroscopy and density functional theory (DFT) calculations demonstrate that annealing processes in vacuum and in ambient air induce a modification in the density of states, resulting in alterations in p‐type or n‐type characteristics. These reversible changes are attributed to the physisorption and elimination of oxygen on the surface of MoTe2. Furthermore, it is found that the device geometry affects the polarity of the transistor. By strategically manipulating both the annealing conditions and the geometric configuration, the n‐ and p‐type unipolar characteristics of MoTe2 FETs are successfully modulated and ultimately demonstrating that the functionality of not only a complementary inverter with a high voltage gain of ≈20, but also more complex logic circuits of NAND and NOR gates. [ABSTRACT FROM AUTHOR]

Monolayer MoTe2 exhibits a variety of derivative structural phases and associated intriguing electronic properties that enable a wealth of potential applications in future electronic and optoelectronic devices. However, a comprehensive study focusing on the complexities of the controllable phase evolution in this atomically thin film has yet to be performed. This work aims to address this issue by systematically investigating molecular beam epitaxial growth of monolayer Mo–Te compounds on bilayer graphene substrates. By utilizing scanning tunneling microscopy, we explored a series of thermally driven structural phase evolutions, including distinct T′-MoTe2, H-MoTe2, Mo6Te6 nanowires, and multistoichiometric MoTe2−x. Furthermore, we carefully investigated the critical effects of the growth parameters—annealing temperature and time and tellurium concentration—on the controllable and reversible phase transformation within monolayer MoTe2−x. The findings have significant implications for understanding the thin film synthesis and phase transformation engineering inherent to two-dimensional crystals, which can foster further development of high-performance devices. [ABSTRACT FROM AUTHOR]

Responsive chiral optical materials have gained considerable interests from the fields of sensing, display, and optical devices. Materials that are capable of changing chiral optics under harsh conditions such as strong basic/acidic or ultrahigh temperature provides thoughts for the design of materials working at special environments, which however, are still underdeveloped. Here, a proof‐of‐concept design of organogel is reported that acts as matrices for thermal chiroptical switch with critical working temperature above 100 °C. The reversible solution‐to‐gel transition of the specific β‐cyclodextrin/dimethyl formide/LiCl system is initialized at about 130 °C, when the luminophores with aggregation‐induced‐emission property shall be lighted up with transferred chirality from inherent chiral β‐cyclodextrin. It allows for the controlled emergence of circularly polarized luminescence. This delicate design enables successful fabrication of ultrahigh temperature thermal chiroptical switch. [ABSTRACT FROM AUTHOR]

To clarify the strengthening mechanisms of medium‐chromium stainless steels (SSs) with carbides, ferrite, and martensite, 17%Cr SSs with varying martensite contents have been prepared, and the influence of martensite on microstructure, mechanical properties, and fracture has been investigated. According to THERMOCALC calculations, 17%Cr SS undergo a reversible phase transition between austenite and ferrite + M23C6 through the diffusion of carbon in austenite and M23C6 in the temperature range of 850–1220 °C. As the martensite content increases, M23C6 decreases, the martensite grain size increases, and the ferrite grain size initially increases and then decreases. Meanwhile, the yield strength and ultimate tensile strength increase, while both the uniform and post‐uniform elongation decrease. It is also found a decrease in work‐hardening index and an increase in work‐hardening rate with increasing martensite content. Under tensile loading, three types of voids are present in 17%Cr SS: type A only in the grain boundary (GB) area with M23C6 in martensite‐free material and type B and C in ferrite grains close to martensite grains and at ferrite/martensite GBs, respectively. An increase in martensite content leads to more voids, indicating a reduction in material plasticity caused by martensite. [ABSTRACT FROM AUTHOR]

The exploration of antibiotic‐independent phototherapy strategies for the treatment of bacterial biofilm infections has gained significant attention. However, efficient eradication of bacterial biofilms remains a challenge. Herein, a self‐regulated phototheranostic nanosystem with single wavelength‐triggered photothermal therapy (PTT)/photodynamic therapy (PDT) transformation and oxygen supply for multimodal synergistic therapy of bacterial biofilm infections is presented. This approach combines a eutectic mixture of natural phase‐change materials (PCMs) and an aggregation‐induced emission (AIE) phototheranostic agent TPA‐ICN to form colloidally stable nanopartcicles (i.e. AIE@PCM NPs). The reversible solid−liquid phase transition of PCMs facilitates the adaptive regulation of the aggregation states of TPA‐ICN, enabling a switch between the energy dissipation pathways for enhanced PDT in solid PCMs or enhanced PTT in liquid PCMs. Additionally, oxygen‐carrying thermoresponsive nanoparticles are also introduced to alleviate the hypoxic microenvironment of biofilms by releasing oxygen upon heating by AIE@PCM NPs with enhanced PTT. The nanosystem exhibits outstanding therapeutic efficacy against bacterial biofilms both in vitro and in vivo, with an antibacterial efficiency of 99.99%. This study utilizes a self‐regulated theranostic nanoplatform with adaptive PTT/PDT transformation via the phase transition of PCMs and heat‐triggered oxygen release, holding great promise in the safe and efficient treatment of bacterial biofilm infections. [ABSTRACT FROM AUTHOR]

With the growing demand for high‐performance smart windows, the discover of a class of thermochromic materials with reversible cycling and rapid response characteristics has become urgent. In this work, we have uncovered a two‐dimensional (2D) Ruddlesden‐Popper (RP) phase halide perovskite, (PMA)2MAPb2I7−xClx, where PMA=C6H5CH2NH3 and MA=CH3NH3, exhibiting exceptional reversible thermochromic properties. The 2D RP phase perovskite thin film features a low transition temperature (Tc=30 °C from the hydrated state to the hot state, along with a fast transition time of 40 s. Furthermore, the addition of 0.5 times excess MAI significantly enhances the visible light transmittance of the hydrated state. Characteristic hydration peaks in X‐ray diffraction patterns and O−H bond absorption peaks Fourier‐transform infrared spectra are observed in the thin film in its hydrated state, which disappear in the hot state, validating its reversible thermochromic properties. Additionally, a solar cell based on the thermochromic 2D RP phase thin film achieves a power conversion efficiency of 2.31 %, offering a promising solution for advanced smart window technologies. [ABSTRACT FROM AUTHOR]

Nanomaterials have been utilized as antibacterial agents due to their distinct mechanism of action, which sets them apart from traditional antibiotics. Cerium oxide nanoparticles (CeO2 NPs) play a crucial role as antibacterial agents because of their minimal toxicity towards healthy cells and their unique antibacterial mechanism, which involves the reversible transition between two valence states of Ce(III)/Ce(IV). In the current study, silica microspheres (SiO2) were applied for the growth of hydroxyapatite (Hap) over the silica surface. Then, the SiO2/hydroxyapatite (SiO2/Hap) nanocomposite was applied for stabilization of the in situ green synthesized cerium oxide nanoparticles (CeO2 NPs) on its surface to assess the antibacterial and cellular viability of orthodontic brackets. The as-prepared SiO2/Hap-CeO2 NPs were fully characterized by different techniques such as FT-IR, XRD, FE-SEM, TEM and ICP-OES analyses. The technique employed to coat the orthodontic bands with SiO2/Hap-CeO2 NPs nanocomposite was the electrostatic spray-assisted vapor deposition method. The antibacterial efficacy of SiO2/Hap-CeO2 NPs nanocomposite against Candida albicans, Streptococcus mutans and Lactobacillus acidophilus was evaluated using the biofilm inhibition test. In the recent study's cellular and molecular component, the treated cells with SiO2/Hap-CeO2 NPs nanocomposite underwent evaluation through MTT assay to determine cytotoxicity on the normal (HUVEC) cell line. In comparison to the control group, the SiO2/Hap-CeO2 NPs nanocomposite group exhibited a 2-log10 decrease in the replication ability of all microorganisms. The group of SiO2/Hap-CeO2 NPs nanocomposite demonstrated a notable decrease in the quantity of C. albicans, S. mutans and L. acidophilus colonies compared to the control group. Application of SiO2/Hap-CeO2 NPs nanocomposite on orthodontic bands resulted in antibacterial properties against oral pathogens. [ABSTRACT FROM AUTHOR]

Low ionic conductivity hinders the practical application of solid polymer electrolytes. Here, an interface‐oscillating polymer electrolyte (IOPE) based on graphdiyne (GDY) is designed and prepared to enable high‐performance all‐solid‐state lithium (Li) metal batteries (ASSLMBs). The affinity of GDY to Li ions induces the competitive adsorption of Li ions, weakens the coordination ability of Li ions with electron‐rich oxygen (on ethylene oxide), and accelerates the Li‐ion migration kinetics. The weak coordination between Li+‐acetylene greatly promotes the rapid reversible transition of GDY itself, resulting in strong self‐expanding/shrinking of the GDY skeleton and the GDY/polymer interface oscillation, and the reduction of the Li‐ion diffusion energy barrier at the interfaces. Consequently, the as‐prepared IOPE shows significantly improved Li‐ion conductivity (1.5 × 10−4 S cm−1 at 35 °C) and transference number, as well as excellent stability toward Li metal anodes. The ASSLMBs assembled with LiFePO4 cathodes and IOPE exhibit excellent rate and cycling performance, capable of stable operation for more than 250 cycles with a high‐capacity retention of 98% at 0.1C (1C = 170 mA g−1). The high‐performance all‐solid‐state Li metal pouch cells are also demonstrated to show great potential for the practical application of IOPE. [ABSTRACT FROM AUTHOR]

Thermal interface materials (TIMs) paly an indispensable role in improving overall performance of chip, due to the boom of cloud service, machine learning, and artificial intelligence. However, traditional TIMs tend to behave as liquid‐like or solid‐like features, which cannot meet the new requirement of both long‐term stability and excellent thermal‐conduction property. Here, a thermally conductive yield stress fluid consisting of phenyl‐vinyl polydimethylsiloxane polymer and aluminum oxide fillers is reported. This material exhibits reversible liquid–solid transition with a yield‐stress value of 87.32 Pa, and low thermal resistance (0.16 K cm2 W−1). The reversible liquid–solid transition and low thermal resistance are both attributed to the formation of the filler network, as demonstrated by using rheology and two‐phase model. Furthermore, a unifying description of the liquid–solid transition is proposed based on a jamming phase diagram, by considering three factors including filler fraction, temperature, and stress. The yield‐stress fluids combine the desired dispensing due to their liquid‐like behavior and the excellent long‐term stability due to their solid‐like feature. An insight is further provided into the application of this yield‐stress fluids in high‐performance TIMs. [ABSTRACT FROM AUTHOR]

Monoclinic VO2 (M) is a material of great significance in the study of correlation effects in solids because of its reversible metal‐insulator phase transition between VO2 (M) and VO2 (R) just above the room temperature. Synthesizing pure monoclinic VO2 (M) can be a challenging task due to the formation of other polymorphs such as VO2 (A), VO2 (B), VO2 (D) and VO2 (P) etc. during the synthesis. Additionally, these synthesis techniques involve complex multistep procedures with protective gas environment and controlled reaction parameters clubbed with elongated reaction time ranging from 1 to 7 days which are major obstacles in the mass production of this material. Here we report a novel and rapid synthetic protocol of VO2 (M) for first time using diethylene triamine (DETA) as a reducing and morphology controlling agent in hydrogen peroxide medium. The detailed characterization of prepared materials confirms the formation of phase pure VO2 (M) crystalline powders. The present approach helps to tune these particles from one‐dimensional rods to two‐dimensional petals like structures. [ABSTRACT FROM AUTHOR]

Hydrogel smart windows with light modulation capability have received widespread attention because they can meet the requirements of indoor lighting at daytime, privacy protection at night and energy saving. However, it remains challenging to achieve these multiple goals simultaneously and enable active actuation to meet the temporary needs of users. In this study, a thermal and solvent responsive hydrogel smart window was developed by introducing hydroxypropyl cellulose (HPC) and sodium dodecyl sulfate (SDS) micelles into a polyacrylamide (PAAm) cross-linked network. By adding different concentrations of NaCl solution, the hydrogels underwent upper critical solution temperature (UCST)- and lower critical solution temperature (LCST)-type phase transitions in the ranges of 1 − 15 °C and 25 − 80 °C, respectively, which enabled the hydrogel to achieve a reversible transition between opacity and transparency with temperature change. The smart window exhibited an excellent solar modulation ability (Tlum = 91.39%, ΔTsol,15−5℃ = 68.67%, ΔTsol,15−40℃ = 62.50%) and effective IR shielding. Furthermore, actively actuated light modulation of hydrogel smart windows was achieved by spraying ethanol on the hydrogel surface. Ethanol stimulation and volatilization induced the reconfiguration and dissociation of hydrogen bonds between HPC and PAAm molecular chains, resulting in reversible transparency transitions. We anticipate that this facile strategy for preparing thermal and solvent responsive hydrogels could serve as a promising alternative for designing phase change hydrogels for a variety of applications. [ABSTRACT FROM AUTHOR]

A newly designed tetracarboxylic acid ligand precursor 5,5'-([9,9'-bianthracene]-10,10'-diyl)diisophthalic acid (H4BADI) has been used to prepare a series of copper-based metal--organic frameworks (MOFs) with the formula [Cu2(BADI)(S)2]•xS (denoted as 1-S, where S = solvent) and exhibiting solvent-induced structural transformations. Single-crystal-to-single-crystal transformation occurs upon exchanging 1-DMF (DMF = N,N-dimethylformamide) with DMSO (DMSO = dimethylsulfoxide). 1-DMF exhibits reversible structural transformation upon treatment with a variety of solvents; of particular interest is the reversible crystalline-to-amorphous phase transformations observed upon exchange with volatile, polar solvents. A thorough structural investigation of the three framework isomers characterized via single-crystal X-ray diffraction experiments is reported and compared to several other tetracarboxylate-based MOFs composed of dimetal secondary building units. [ABSTRACT FROM AUTHOR]

Microfluidics and droplet-based assays are the basis for numerous high-throughput experiments, including bio-inspired microreactors and selection platforms for directed evolution. While elaborate techniques are available for the production of picoliter-sized droplets, there is an increasing demand for subsequent manipulation and control of the droplet interior. Here, we report on a straightforward method to rapidly adjust the size of single to several hundred double-emulsion droplets in a microfluidic sieve by varying the carrier fluid's salt concentration. We show that the concomitant concentration changes in the droplet interior can drive a reversible demixing transition in a biomimetic binary fluid. As another application, we show that growing and shrinking of trapped droplets can be utilized to achieve a reversible dissociation of double-stranded DNA into single strands, i.e. cycles of reversible DNA hybridization, similar to PCR cycles, can be achieved by reversibly changing the droplet size at constant temperature. Altogether, our approach shows how a simple and temporally tunable manipulation of the size and the chemistry in prefabricated droplets can be achieved by an external control parameter. [ABSTRACT FROM AUTHOR]

All‐inorganic metal halides have merged as auspicious materials for optoelectronic applications due to their predominant tunable and controlled photoluminescence (PL) properties. Despite substantial efforts and advances in the development of these all‐inorganic metal halides, considerable long‐term challenges remain to be solved to realize cutting‐edge material performances. Here, an all‐inorganic metal halide RbCdCl3, featuring a reversible structural phase transformation from non‐perovskite (orthorhombic‐phase) to perovskite (tetragonal‐phase) structure is reported. Intriguingly, via phase transformation regulation engineering, a near‐unity photoluminescence quantum yield (PLQY) along with large Stokes shift (275 nm) and long decay lifetime (14.69 ms) is achieved in RbCdCl3:Mn2+ thermochromic fluorescent materials, comparing with the pristine non‐pervoskite structure with an initial PLQY of 3.1%. Moreover, the underlying PL switching mechanisms are systematically elucidated by the in situ optical characterizations and the first‐principles calculations. This work demonstrates a thermochromic fluorescent anti‐counterfeiting material based on the tunable and reversible photoluminescence switching and also provides a phase structure engineering in metal halides to broaden their manifold applications in optoelectronic fields. [ABSTRACT FROM AUTHOR]

Reversible solid oxide cells (r -SOCs) are regarded as a solution form of clean energy generation towards a green hydrogen energy transition. However, during transportation, installation, and operation, they are required to withstand dynamic conditions as they face thermal, mechanical, and vibrational effects. Assessing the interplay of the thermomechanical and dynamical impacts on r-SOC materials during the mode-switch from electrolysis to fuel cell operation is the subject of this current comprehensive study. Advanced FEM-based homogenisation techniques have been harnessed in predicting and evaluating the detailed transients during static and dynamic loading. The intricate 3D thermal profiles throughout the transient reversible dual-modus operation from a typical r-SOC study have been derived using advanced image processing. Orthotropic material properties were incorporated into a unified macroscopic scale model by deriving the complex 3D microstructure geometry characteristics of the cell materials and component layers. The comprehensive thermomechanical and pre-stressed modal analysis results showed that the static and dynamic forces in fuel cell mode are more pronounced, whereas, in electrolysis operation, the dynamical behaviour highly depends on geometrical and operating conditions. Smaller component size shows higher natural frequencies and more intense vibration, leading to higher deformation attributed to complex mode shapes and reduced flexural rigidity. These insights are essential for optimizing r-SOC design parameters, enhancing their dynamic and structural reliability throughout their dual-mode operation lifespan. • Influence of cell size and thickness on static and dynamic r-SOC behaviour. • 3D physical r-SOC microstructure model generation and virtually characterisation. • Thermal field derivation using data recognition and image processing techniques. • 3D thermomechanical stresses, natural frequencies, and mode shapes are determined. • Comparison of thermomechanical and dynamic effects on reversible operation. [ABSTRACT FROM AUTHOR]

Thermochromic luminescent materials (TLMs) with spectral responsiveness to thermal stimuli have received broad attention due to the forefront applications in temperature visualization and sensing technologies. Herein, a phase diagram‐driven strategy for designing TLMs in Cs–Cd–Br ternary system is presented. The room temperature stable Cs7Cd3Br13 crystal is first obtained by utilizing a facile hydrothermal method, and the self‐trapped exciton (STE) luminescence is improved by breaking local symmetry via Mg2+ doping. Then thermochromic luminescence is further realized in Mn2+ co‐doped Cs7Cd3Br13 on the basis of reversible structural transition to metastable Cs2CdBr4 under thermal stimuli. The emission color change from bright yellow to green benefits from the variation of crystal fields around Mn2+, which can be switched by heating and cooling circulations. Finally, the resulting material is used as a demo to visualize the temperature of a homemade high‐frequency induction heating sintering platform. [ABSTRACT FROM AUTHOR]

Layered oxides are considered to be potential cathodes for sodium‐ion batteries based on high theoretical capacity and ease of synthesis. However, the complex phase transition caused by interlayer sliding in layered oxides leads to poor cycling stability, which will hinder their further application. Here, we designed a newly O3‐type layered cathode NaNi0.3Co0.2Cu0.1Mn0.2Ti0.2O2 based on high‐entropy to achieve highly reversible phase transition behavior. It reveals 132 mAh g−1 at 0.2 C within 2–4 V increasing the energy density to 408 Wh kg−1 and it shows an outstanding rate capability of 90 mAh g−1 at 80 C (84.90% capacity retention after 1,500 cycles at 80 C). In‐situ XRD shows that reasonable design of high‐entropy components in layered material can achieve the purpose of delaying the occurrence of phase transition and DFT calculations show that the introduction of Co in transition metal layers can effectively improve the rate performance of the material. This work is of great significance in guiding the design and synthesis of highly stable layered cathode materials for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

BaAl 2 Si 2 O 8 (barium feldspar-based) materials are widely used in glass and ceramic industry due to high melting temperature, chemical resistance, low thermal expansion, low dielectric constants and attractive luminescence properties. The durability of barium feldspar ceramics strongly depends on reversible phase transitions between the low-temperature modification (celsian), and series of high-temperature (HT) polymorphs known as 'hexacelsian'. Numerous works have been devoted to the study of the thermal transitions of 'hexacelsian' by X-ray powder diffraction methods and transmission electron microscopy, the use of which provides limited information about structural changes. Here, the crystal structures, thermal properties and phase transitions of HT BaAl 2 Si 2 O 8 polymorphs are characterized for the first time using in-situ HT X-ray single-crystal structural study (SCXRD), and micro-Raman spectroscopy up to 1000 °C. The crystal structure of α-hexacelsian under ambient conditions is monoclinic (I 2/ a). The alpha-form undergoes two polymorphic transformations upon heating: into an orthorhombic (Fmmm) β-modification above 300 °C and into a hexagonal (P –62 m) γ-modification above 700 °C. These transitions lead to significant changes in the unit-cell volume: an obstacle in the production of BaAl 2 Si 2 O 8 -based ceramics. [ABSTRACT FROM AUTHOR]

The formation of cristobalite thermally grown oxides (TGO) is a major life limiting factor for environmental barrier coatings (EBCs) with Si bond coat exposed to high temperature steam environments due to its reversible phase transformation and the resultant cracking behaviour during thermal cycling. Therefore, controlling or avoiding cristobalite TGO formation by engineering coating chemistry and architecture will be desirable for a highly durable EBC system. In this work, a multilayer Si/Al-Si-N/Yb 2 Si 2 O 7 EBC was produced using a hybrid vapor deposition process. The oxidation behavior of the EBC was evaluated in flowing 90% H 2 O (g) + 10% air at 1316 °C. After 100 h and 510 h steam test, crack-free mullite and Al-Si-O-N layers formed above Al-Si-N layer and no SiO 2 scale formation of Si bond coat was observed. Detailed TEM analyses show that the Al-Si-N layer successfully prevented the oxidation of underlying Si bond coat and avoided the formation of detrimental cristobalite phase. [ABSTRACT FROM AUTHOR]

This study examined the gel formation behavior and temperature-dependent mechanical characteristics of gel-cast alumina–agar mixtures. The shift from viscoelastic to elastic behaviors, the influence of final agar content, the reversibility of the viscoelastic–elastic transition, and the relationship between complex modulus and temperature were all investigated. The complex viscosity of the mixtures was also investigated to determine their role in ceramic shaping operations. The findings are useful for academics and practitioners in materials science and engineering, especially those who work with alumina–agar mixtures. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations were conducted to explore nanoindentation-induced martensitic transformation in NiTi shape memory alloys. Three atomic compositions and two indenter sizes were considered. During loading, the B2 structure underwent martensitic transformation to the B19' structure, accompanied by atomic rearrangement in the form of bands. After unloading, a portion of the B19' phase underwent reversible transformation, while the remainder remained in the form of bands, resulting in residual strain. This effect was accentuated by the more localised deformation promoted by the smaller indenter. The influence of atomic composition was observed not to play a key role in the mechanical and structural properties, contrary to previous reports on tension and compression tests. Our findings shed light on the intricate interplay of factors influencing the mechanical performance of NiTi shape memory alloys at the atomic scale, providing crucial insights for the design and understanding of such materials. [ABSTRACT FROM AUTHOR]

Chiral self‐discrimination plays a critical role in supramolecular chemistry and materials science. However, an ideal strategy for achieving chiral self‐discrimination remains elusive due to the inevitable nonspecific binding of incorrect enantiomers, and insufficient intrinsic optical activity of chiral molecules. Herein, a novel 1,1′‐binaphthol (BINOL) derivative with an imide group fused at the peri‐position of one naphthol scaffold is developed, which combines the dual functionalities of aggregation‐induced emission characteristic of BINOLs, and high emission of 1,8‐naphthalimides. The multiple molecular recognition between two hydroxyl groups in BINOL units and two carbonyl groups in 1,8‐naphthalimide moieties endows the precise chiral self‐discrimination behaviors. As expected, the homochiral aggregates exhibit reversible phase transitions, switching from non‐emission to bright green emission upon absorption and desorption of methanol vapor. In contrast, the heterochiral conglomerates exhibit irreversible yellow emission changes due to the impact of chiral self‐discrimination. Such chiral self‐discrimination‐induced luminescence vapochromism can be further applied to high‐level anti‐counterfeiting and data encryption. This work provides a new perspective on smart chiral organic materials based on chiral self‐discrimination. [ABSTRACT FROM AUTHOR]

Individual differences in size, experience, and task specialization in natural swarms often result in heterogeneity and hierarchy, facilitating efficient and coordinated task accomplishment. Drawing inspiration from this phenomenon, a general strategy is proposed for organizing magnetic micro/nanorobots (MNRs) with apparent differences in size, shape, and properties into cohesive microswarms with tunable heterogeneity, controlled spatial hierarchy, and collaborative tasking capability. In this strategy, disparate magnetic MNRs can be manipulated to show reversible transitions between synchronization and desynchronization by elaborately regulating parameter sets of the rotating magnetic field. Utilizing these transitions, alongside local robust hydrodynamic interactions, diverse heterospecific pairings of disparate magnetic MNRs can be organized into heterogeneous microswarms, and their spatial organization can be dynamically adjusted from egalitarian to leader‐follower‐like hierarchies on the fly, both in open space and complex microchannels. Furthermore, when specializing the disparate MNRs with distinct functions ("division of labor") such as sensing and drug carrying, they can execute precise drug delivery targeting unknown sites in a collaborative sensing‐navigating‐cargo dropping sequence, demonstrating significant potential for precise tumor treatment. These findings highlight the critical roles of attribute differences and hierarchical organization in designing efficient swarming micro/nanorobots for biomedical applications. [ABSTRACT FROM AUTHOR]

By introducing disordered molecules into a crystal structure, the motion of the disordered molecules easily induces the formation of multidimensional frameworks in functional crystal materials, allowing for structural phase transitions and the realization of various dielectric properties within a certain temperature range. Here, we prepared a novel ionic complex [C7H8N3]3[Fe(NCS)6]·H2O (1) between 2-aminobenzimidazole and ferric isothiocyanate from ferric chloride hexahydrate, ammonium thiocyanate, and 2-aminobenzimidazole using the evaporation of the solvent method. The main components, the single-crystal structure, and the thermal and dielectric properties of the complex were characterized using infrared spectroscopy, elemental analysis, single-crystal X-ray diffraction, powder XRD, thermogravimetric analysis, differential scanning calorimetry, variable-temperature and variable-frequency dielectric constant tests, etc. The analysis results indicated that compound 1 belongs to the P21/n space group. Within the crystal structure, the [Fe(NCS)6]3− anion formed a two-dimensional hydrogen-bonded network with the organic cation through S···S interactions and hydrogen bonding. The disorder–order motion of the anions and cations within the crystal and the deformation of the crystal frameworks lead to a significant reversible isostructural phase transition and multiaxial dielectric anomalies of compound 1 at approximately 240 K. [ABSTRACT FROM AUTHOR]

The template wetting method is a common method used for preparing one‐dimensional polymer nanostructures, which can be widely applied in many fields. Although the template wetting method has generality in controlling the morphology of nanomaterials, it still poses challenges in generating patterned polymer nanoarrays. Here, we present the fabrication of patterned and anti‐patterned azopolymer (PAzo) nanoarrays via the light‐induced nanowetting method. By shining UV lights, the trans‐PAzo converts to cis‐PAzo, causing a reduction of the glass transition temperature (Tg) of the PAzo below room temperature. Consequently, the PAzo polymers can undergo reversible solid–liquid transitions by shining UV and visible lights. When PAzo films are covered with photomasks and anodic aluminum oxide (AAO) templates, followed by shining UV lights, patterned PAzo nanoarrays can be generated. We further apply the concept that cis‐PAzo films can be selectively removed by solvents to generate anti‐patterned PAzo nanoarrays. By covering PAzo films with photomasks and illuminating UV lights, the unmasked areas can be converted to cis‐form, which can then be selectively removed by selected solvents. The patterned PAzo films are then covered with AAO templates, followed by shining UV lights, forming hierarchical anti‐patterned PAzo nanoarrays. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, we introduce a hydrogel-polymer microsphere (HPM) composite material constituted of PVA, glycerin, and polymer microspheres obtained from Pickering emulsions that are capable of adsorbing Cu2+ ions. The obtained HPM composite is soft, flexible, can be fully saturated with Cu2+ ions, and exhibits a reversible color transition from blue to black upon electrode contact or interaction with a reducing agent, due to in situ generation of copper nanoparticles (Cu-NPs). Because of the color contrast between the locally generated Cu-NPs and the background, the HPM can be used as substrate for stamping different shapes or writing text. Further, the surface can be erased by an acidic solution, which makes it interesting as flexible write-erase displays. A second feature of the HPM is that it can function as a fluorescence detector of cyanide ions. An HPM whose surface has been stamped with an electrode, upon contacting an aqueous solution containing cyanide ions, begins fluorescing a yellow-green light around the patterned area. The displayed luminescence is irreversible and is preserved even after HPM's drying or lyophilization. This work lays a foundational framework for future exploration of the HPM composites in various technological applications, for sensing, circuit printing, and flexible displays. [ABSTRACT FROM AUTHOR]

We report azopyrazole photoswitches decorated with variable N‐alkyl and alkoxy chains (for hydrophobic interactions) and phenyl substituents on the pyrazoles (enabling π‐π stacking), showing efficient bidirectional photoswitching and reversible light‐induced phase transition (LIPT). Extensive spectroscopic, microscopic, and diffraction studies and computations confirmed the manifestation of molecular‐level interactions and photoisomerization into macroscopic changes leading to the LIPT phenomena. Using differential scanning calorimetric (DSC) studies, the energetics associated with those accompanying processes were estimated. The long half‐lives of Z isomers, high energy contents for isomerization and phase transitions, and the stability of phases over an extended temperature range (−60 to 80 °C) make them excellent candidates for energy storage and release applications. Remarkably, the difference in the solubility of the distinct phases in one of the derivatives allowed us to utilize it as a photoresist in photolithography applications on diverse substrates. [ABSTRACT FROM AUTHOR]

Cadmium telluride (CdTe) is a highly promising material for photovoltaics (PV) and photodetectors due to its light‐absorbing properties. However, efficient design and use of flexible devices require a deep understanding of its atomic‐level deformation mechanism. Herein, uniaxial compression deformation of CdTe monocrystalline with varying crystal orientations is investigated using molecular dynamics (MD) with a newly developed machine‐learning force field (ML‐FF), alongside in‐situ micropillar compression experiments. The findings reveal that CdTe bulk deformation is dominated by reversible martensitic phase transformation, whereas CdTe pillar deformation is primarily driven by dislocation nucleation and movement. CdTe monocrystals possess exceptional super‐recoverable deformation along the <100> orientation due to hyper‐elastic processes induced by martensitic transformation. This discovery not only sheds light on the peculiarities observed in micropillar experimental measurements, but also provides pivotal insights into the fundamental deformation behaviors of CdTe and similar II–VI compounds under various stress conditions. These insights are crucial for the innovative design and enhanced functionality of future flexible electronic devices. [ABSTRACT FROM AUTHOR]

In order to better understand the memristive characteristics of Ag/1%(Co, Li)-co-doped ZnO/Pt/Si–SiO2 devices, this work looks at possible uses of dual-doped materials-based memory for neuromorphic computing. Transmission electron microscopy (TEM) was used to study the device structure after a 70-nm thin layer of 1% (Co, Li)-co-doped ZnO was formed on a Si–SiO2 substrate using a sputtering technique. The set and reset voltages of 1.22 V and 1.01 V, respectively, were demonstrated by the devices, which demonstrated dependable repeatable resistance switching for 80 cycles. Analyzing conductance modulation with recurrent both positive and negative pulses revealed depression and potentiation curves that were almost linear. In order to clarify the switching process, a physical model was put out that focused on the oxidation–reduction reactions that drive the production and rupture of Ag conductive filaments in the presence of an applied electric field. The device's usefulness for neuromorphic computing systems is highlighted by its reversible transitions between high and low resistance states and its steady and symmetric I–V properties. These results imply that (Co, Li)-co-doped ZnO memristors are good options for creating dependable and effective memory technologies. [ABSTRACT FROM AUTHOR]

Anionic redox chemistry is now viewed as the effective paradigm of improving the capacity of layered oxide materials in Sodium‐ion battery. In this study, O3‐type layered oxide NaLi0.18Co0.23Ru0.59O2 (NLCR) with O redox ability is successfully synthesized via a facile solid‐state synthesis method. By manipulating the calcinate atmosphere with air and argon (sort by NLCR‐Air NLCR‐Ar respectively), a large amount of O vacancy is introduced in the NLCR‐Air cathode. NLCR‐Air with sufficient O vacancy exhibited superior rate performance which showed 87.7% capacity retention after 1000 cycles at 20 C. Both NLCR‐Air and NLCR‐Ar showed activation of O redox properties which is supported by the soft X‐ray absorption spectroscopy (sXAS). Nevertheless, the in‐situ X‐ray diffraction and sXAS studies disclosed the O vacancy can promote the reversible phase transition and effectively suppress the irreversible O redox upon cycling. These are further supported by theoretical study which suggested a fast kinetic of Na diffusion and less electron agglomeration around the O atom for NLCR‐Air with O vacancy.The research proposed a modification strategy with extraordinary reversible O redox property within O3‐type layered cathode and offered a novel insight into understanding the anionic redox mechanism thus provide guidance of material design advanced energy storage systems. [ABSTRACT FROM AUTHOR]

Hg-based compounds show abundant structural diversity and distinguished properties. Herein, a new phase transition compound CsHg2I5 was reported. The high-temperature phase β-CsHg2I5 with rare [Hg2I5] dimers was synthesized by the flux method at 573 K, and it shows a reversible phase transition at a low temperature of ∼100 K to form the low-temperature phase α-CsHg2I5. The two phases crystallize in the same P21/c space group, with different crystal structures. β-CsHg2I5 is composed of rare [Hg2I5] dimers and [CsI11] polyhedral units, while α-CsHg2I5 is composed of [Hg4I11] and [CsI10] units. The experimental band gap of β-CsHg2I5 was found to be 2.58 eV. Owing to the presence of [Hg2I5]∞ pseudo-layers, β-CsHg2I5 exhibits large optical anisotropy with a calculated birefringence of 0.132@1064 nm. Meanwhile, β-CsHg2I5 is a congruent compound and the congruent point is ∼481 K. Theoretical calculations indicate that the rare [Hg2I5] dimer is a nonlinear active unit, which can be used as a new fundamental building block for the design of advanced nonlinear optical materials. Moreover, a CsI–HgI2 pseudo-binary diagram was drawn. The results enrich the structural diversity of Hg-based halides and give some insights into the development of new functional materials based on rare [Hg2I5] dimers. [ABSTRACT FROM AUTHOR]

First example of a Zr(IV) complex with an aromatic carboxyamidate ligand, Zr(mba)4 (mba = N-methoxybenzamidate), is prepared. Its structures in the solution (1H, 13C{1H} NMR) and in the crystal phase (single-crystal XRD) are determined and compared with those of the initial N-methoxybenzamide Hmba. During the complexation, mba– ligands exhibit a bidentate cyclic function through oxygen atoms. The coordination polyhedron of the metal atom is a distorted square antiprism, the lengths of Zr–O bonds with carbonyl and methoxy groups fall within 2.08-2.09 Å and 2.29-2.33 Å, respectively. Despite the presence of available phenyl rings, the Zr(mba)4 and Hmba crystals contain no intermolecular π–π-interactions, but exhibit C–H⋯π and N–H⋯O contacts, respectively. According to the DSC data, Hmba undergoes no phase transitions from 130 K up to the melting point (335.0±0.5 K, ΔH = 15.1±0.1 kJ/mol, ΔS = 45.2±0.2 J/(mol·K)), while Zr(mba)4 exhibits a reversible solid-phase transition (Tonset = 177.4±0.5 K, ΔH = 0.68±0.20 kJ/mol, ΔS = 3.8±0.1 J/(mol·K)). Studying the Zr(mba)4 crystals at 150 K and 200 K shows that this transition is not accompanied by the crystal deformation and is apparently caused by the rotation of phenyl groups. Due to this conversation, the space group changes from P21/c to P21/n, and one of the unit cell parameters increases by 3 times. [ABSTRACT FROM AUTHOR]

The development of 1D stimuli‐responsive ultrathin organic nanomaterials (UTONMs)‐based hybrid nanocomposites with tailored functions is necessitated to construct hybrid catalysts with adjustable catalytic performance. Herein, the self‐assembly of ternary amphiphilic alternating azopeptoids into micron‐scaled ultrathin peptoid nanobelts (PNBs) is reported with a thickness of ≈2.2 nm. The pendants hydrophobic conjugate stacking mechanism is accountable for the formation of 1D long‐ranged‐ordered nanostructure, whose thickness is highly dependent on the length of the suspended side‐chains. The photo‐triggered reversible transition from PNBs to nanospheres (≈92 nm) is rendered by the photo‐isomerization of azobenzene moiety upon alternating irradiation with UV and visible lights. Moreover, the carboxyl‐modified aggregates are employed as supports to load Pd nanoparticles, successfully preparing hybrid nanocomposites. As a proof‐of‐concept experiment, the catalytic activity of both control and these hybrid nanocomposites are evaluated toward chemo‐enzymatic cascade catalysis for 3,3′,5,5′‐tetramethylbenzidine oxidation with in situ UV–vis spectroscopic monitor. Compared to nanospheres‐based systems, PNBs‐based nanocomposites exhibited larger catalytic performance, attributable to the ultrathin nanostructures and subsequent ultrahigh specific surface area. The photo‐controllable recyclable catalytic activity is effectively modulated using the alternative irradiation with UV and visible lights for three cycles. The work paves an appealing avenue to prepare UTONMs‐based stimuli‐responsive hybrid nanocomposites with controllable performance. [ABSTRACT FROM AUTHOR]

Thermochromic smart windows realize an intelligent response to changes in environmental temperature through reversible physical phase transitions. They complete a real-time adjustment of solar transmittance, create a livable indoor temperature for humans, and reduce the energy consumption of buildings. Nevertheless, conventional materials that are used to prepare thermochromic smart windows face challenges, including fixed transition temperatures, limited solar modulation capabilities, and inadequate mechanical properties. In this study, a novel thermochromic hydrogel was synthesized from 2-hydroxy-3-butoxypropyl hydroxyethyl celluloses (HBPEC) and poly(N-isopropylacrylamide) (PNIPAM) by using a simple one-step low-temperature polymerization method. The HBPEC/PNIPAM hydrogel demonstrates a wide response temperature (24.1–33.2 °C), high light transmittance (Tlum = 87.5%), excellent solar modulation (ΔTsol = 71.2%), and robust mechanical properties. HBPEC is a functional material that can be used to adjust the lower critical solution temperature (LCST) of the smart window over a wide range by changing the degree of substitution (DS) of the butoxy group in its structure. In addition, the use of HBPEC effectively improves the light transmittance and mechanical properties of the hydrogels. After 100 heating and cooling cycles, the hydrogel still has excellent stability. Furthermore, indoor simulation experiments show that HBPEC/PNIPAM hydrogel smart windows have better indoor temperature regulation capabilities than traditional windows, making these smart windows potential candidates for energy-saving building materials. [ABSTRACT FROM AUTHOR]

Thixotropic yield-stress fluids (TYSFs) are a unique class of materials whose properties are affected by both shear rate and shear history. When sheared, these materials undergo a transition from an elastic solid to a viscoelastic fluid, which is accompanied by a structural transition that slowly recovers upon the cessation of shear. The strong interdependence between structure, dynamics, and rheological properties in TYSFs make it challenging to identify the fundamental physics controlling these phenomena. In this study, we vary the ionic strength of a suspension of cellulose nanocrystals (CNC) to generate model TYSFs with tunable moduli and thixotropic kinetics. We use a novel rheological protocol—serial creep divergence—to identify the physics underlying the yield transition and recovery of CNC gels. Our protocol identifies a critical transition that bifurcates the solid-like and fluid-like regimes of the gels to precisely determine the yield stress of these materials even in the presence of thixotropic effects. Additionally, the thixotropic kinetics collapse onto a single master curve, which we fit to a transient solution to a coupled diffusion–aggregation model. Our work thereby identifies the underlying physicochemical mechanisms driving yielding and thixotropic recovery in attractive colloidal gels. [ABSTRACT FROM AUTHOR]

This paper presents the experimental evidence of reversible insulator–metal transition (IMT) in thin-film amorphous molybdenum trioxide (MoO3) induced by electric fields of just a few volts. The presence of oxygen vacancies in MoO3 is considered to play a significant role in the reported reversible IMT. The oxygen vacancies not only impact MoO3 stoichiometry but also the optical bandgap. The subthreshold slope for IMT in 10 nm-thick MoO3-based devices is 48.3 mV/decade, which represents a transition from an insulator to a metallic state, and the electric field threshold for such a transition was found to be equal to 0.034 V/Å. Following the IMT in MoO3, there are six orders of magnitude differences between the resistivity of the insulator state (27.5 M Ω at −9 V) and the metallic state (80 Ω between +5 and +9 V). In addition, we reported stabilization of a nanocrystalline hexagonal MoO3 (h-MoO3) phase in thicker MoO3 (150 nm-thick) in the presence of oxygen vacancies that behave as a wide bandgap (3.1 eV) ferroelectric semiconductor with a coercive field of about 50 kV/cm, a saturation polarization of about 30 μC/cm2, and a remanent polarization of about 10 μC/cm2. This ferroelectricity in nanocrystalline h-MoO3 (150 nm-thick) remains stable even after 8 months of storage of the sample in ambient conditions, with remanent polarization increasing up to 20 μC/cm2. These are unexpected results from MoO3. [ABSTRACT FROM AUTHOR]

We develop and harness a phase field simulation method to study liquid filling on grooved surfaces. We consider both short-range and long-range liquid–solid interactions, with the latter including purely attractive and repulsive interactions as well as those with short-range attraction and long-range repulsion. This allows us to capture complete, partial, and pseudo-partial wetting states, demonstrating complex disjoining pressure profiles over the full range of possible contact angles as previously proposed in the literature. Applying the simulation method to study liquid filling on grooved surfaces, we compare the filling transition for the three different classes of wetting states as we vary the pressure difference between the liquid and gas phases. The filling and emptying transitions are reversible for the complete wetting case, while significant hysteresis is observed for the partial and pseudo-partial cases. In agreement with previous studies, we also show that the critical pressure for the filling transition follows the Kelvin equation for the complete and partial wetting scenarios. Finally, we find the filling transition can display a number of distinct morphological pathways for the pseudo-partial wetting cases, as we demonstrate here for varying groove dimensions. [ABSTRACT FROM AUTHOR]

Breast cancer constitutes a significant global health burden, while conventional diagnosis approaches may lack precision and can be discomforting for patients. Exosomes have emerged as promising biomarkers for breast cancer due to their participation in diverse pathological processes, and a convenient analysis platform is believed to greatly promote its application. In this study, we propose a novel digital PCR approach utilizing near‐infrared (NIR) photo‐responsive thermosensitive microcarriers integrated with black phosphorus for quantifying microRNA (miRNA) biomarkers within exosomes. Petal‐like biomimetic nanomaterials were firstly assembled for non‐specific exosome capture based on the affinity effect of avidin and biotin. Photothermal‐responsive microcarriers, fabricated using gelatin‐based substrates blended with photothermal nanocomposite, exhibited NIR‐induced heating and reversible phase transition properties. We optimized synthesis parameters on thermal response and established a programmable and controllable NIR light source module. The results indicated a significant elevation in the levels of biomarkers miRNA‐1246 and miRNA‐122, with fold increases ranging from 6.2 to 23.6 and 5.9 to 13.0, respectively, in breast cancer cell lines MCF‐7 and MDA‐MB‐231 compared to healthy control cells HUVEC. This study offers broad prospects for utilizing exosomes to resolve predictive biomarkers. [ABSTRACT FROM AUTHOR]

Precise identification and thermodynamic assessment of the various phases in spent nuclear fuel are necessary for the accurate dynamic modeling of nuclear fuel. The Thermodynamics of Advanced Fuels – International Database (TAF-ID) compiles high-quality, self-consistent, and reliable thermodynamic data of various phases in chemical systems of interest for the international nuclear industry, such as the Ba-Mo-O ternary system. The thermodynamic properties of compounds in the Ba-Mo-O ternary system, especially those of hexavalent Mo, have been extensively studied and included in computational thermodynamic assessments. In contrast, compounds with Mo in reduced oxidation states, such as BaMo 6 O 10 and Ba 3 Mo 18 O 28 , have been excluded from such assessments due to a lack of experimentally assessed thermodynamic data. In this work, high-quality samples of the aforementioned compounds were synthesized, and the first experimental assessment of their heat capacities in the temperature range 300–600 K were obtained. Furthermore, a reversible phase transition was identified at ∼380 K for BaMo 6 O 10. The collected experimentally-assessed thermodynamic data from this work and initial calculated estimations of standard enthalpies of formation and entropies for these compounds were successfully integrated into a preliminary, updated Ba-Mo-O thermodynamic assessment using the CALPHAD method. Key thermodynamic properties of the newly included compounds (i.e. , standard enthalpy of formation and entropy) were calculated using the new Ba-Mo-O assessment. [Display omitted] [ABSTRACT FROM AUTHOR]

In recent years, lead-free Bi 0.5 Na 0.5 TiO 3 (BNT) based piezoelectric ceramics with excellent strain properties have gained widespread recognition for their application in high-precision displacement actuators. The (1- x)(0.82Bi 0.5 Na 0.5 TiO 3 -0.18K 0.5 Bi 0.5 TiO 3)- x Ba(Fe 0.5 Sb 0.5)O 3 ceramics were fabricated through the die-pressing method in this work. The effect of BFS introduction on the dielectric, ferroelectric and microstructure characteristics of BNKT ceramics was systematically investigated. Among these compositions, the BNKT-0.015BFS ceramics exhibited a piezoelectric strain coefficient (d 33 *) of 658 pm/V at an electric field of 55 kV/cm, while achieving a strain response of 0.51 % at 85 kV/cm. The observed improvement in strain performance can be attributed to the evolution from non-ergodic relaxor state to ergodic relaxor state caused by BFS substitution. Furthermore, transmission electron microscopy (TEM) explicitly confirmed coexistence of rhombohedral and tetragonal phase and revealed the morphology of nanosized domains. This study adds to a deeper comprehension of the characteristics of strain response enhancement in BNT-based ceramics, opening up avenues for designing novel lead-free piezoelectric ceramics with outstanding electromechanical performance. [ABSTRACT FROM AUTHOR]