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Hypothesis The process of dried blood spot sampling involves simultaneous spreading and penetration of blood into a porous filter paper with subsequent evaporation and drying. Spreading of small drops of blood, which is a non-Newtonian liquid, over a dry porous layer is investigated from both theoretical and experimental points of view. Experiments and theory A system of two differential equations is derived, which describes the time evolution of radii of both the drop base and the wetted region inside the porous medium. The system of equations does not include any fitting parameters. The predicted time evolutions of both radii are compared with experimental data published earlier. Findings For a given power law dependency of viscosity of blood with different hematocrit level, radii of both drop base and wetted region, and contact angle fell on three universal curves if appropriate scales are used with a plot of the dimensionless radii of the drop base and the wetted region inside the porous layer and dynamic contact angle on dimensionless time. The predicted theoretical relationships are three universal curves accounting satisfactorily for the experimental data. [ABSTRACT FROM AUTHOR]

In this paper, we design a binder GG-CA-GLY (abbreviation: GGC) for silicon negative electrode by guar gum as the backbone chain with self-healing function, combing and straightening the guar molecular chain of guar gum through the plasticizing effect of glycerol. The condensation reactions between the exposed hydroxyl sites of guar gum and the carboxyl groups of citric acid create a stronger hydrogen bond, so as to achieve the effect of self-healing and cope with the serious volume expansion effect of silicone-based materials. [Display omitted] • A easy polycondensation reaction is used to create a mechanically strong self-healing polymer (GGC). • GGC adhesives have excellent mechanical properties and facilitate rapid self-healing. • GGC@Si electrodes were prepared with excellent rate capability and higher cycling stability. • GGC adhesives have the ability to repair cracks and other damage on prepared silicon anodes, returning them to their original state. Silicon is a promising anode material for lithium-ion batteries with its superior capacity. However, the volume change of the silicon anode seriously affects the electrode integrity and cycle stability. The waterborne guar gum (GG) binder has been regarded as one of the most promising binders for Si anodes. Here, a unique steric molecular combing approach based on guar gum, glycerol, and citric acid is proposed to develop a self-healing binder GGC, which would boost the structural stability of electrode materials. The GGC binder is mainly designed to weaken van der Waals' forces between polymers through the plasticizing effect of glycerol, combing and straightening the guar molecular chain of GG, and exposing the guar hydroxyl sites of GG and the carboxyl groups of citric acid. The condensation reaction between the hydroxyl sites of GG and the carboxyl groups of citric acid forms stronger hydrogen bonds, which can help achieve self-healing effect to cope with the severe volume expansion effect of silicone-based materials. Silicon electrode lithium-ion batteries prepared with GGC binders exhibit outstanding electrochemical performance, with a discharge capacity of up to 1579 mAh/g for 1200 cycles at 1 A/g, providing a high capacity retention rate of 96%. This paper demostrates the great potential of GGC binders in realizing electrochemical performance enhancement of silicon anode. [ABSTRACT FROM AUTHOR]

[Display omitted] As a good alternative for natural enzyme, enzyme mimics with artificial functional materials have attracted considerable attention. However, it remains a great challenge to develop a facile method to design laccase mimic with high catalytic activity, long-term stability and reusability. In this report, we propose the one-pot synthesis of reusable paper filter templated Cu-doped polydopamine membranes (PF@PDA/Cu) with laccase-like activity. Compared with the natural laccase, the PF@PDA/Cu membrane exhibits enhanced catalytic activity for the chemical conversion of hydroquinone into benzoquinone. Interestingly, these membranes present good tolerance to high temperature and the catalytic activity increases with the increase of temperature. Moreover, these membranes could be stored for 7 days and recycled for 5 times with negligible loss of catalytic activity. This work provides a promising paradigm for rational design and practical applications of metal-loading PDA materials based on one-pot synthesis methodology. [ABSTRACT FROM AUTHOR]

Paper-based materials have attracted a great deal of attention in sensor applications because they are readily available, biodegradable, inexpensive, and mechanically flexible. Although paper-based sensors have been developed, but important obstacles remian, which include the retention of chemical and mechanical stabilities when paper is wetted. Herein, we develop a simple and scalable process for fabrication of newspaper-based platforms by coating of parylene C and patterning of metal layers. As-prepared parylene C-coated newspaper (PC-paper) provides low-cost, disposable, and mechanically and chemically stable electrochemical platforms for the development of potentiometric ion sensors for the detection of electrolyte cations, such as, H + and K + . The pH and K + sensors produced show near ideal Nernstian sensitivity, good repeatability, good ion selectivity, and low potential drift. These disposable, flexible ion sensors based on PC-paper platforms could provide new opportunities for the development of point-of-care testing sensors, for diagnostics, healthcare, and environment testing. [ABSTRACT FROM AUTHOR]

[Display omitted] Using renewable biomass resources to regulate the growth and properties of catalysts is sustainable nanotechnology for achieving efficient photocatalysis and recycling. This work suggested a way to produce paper-based photocatalysts and resize the embedded zinc oxide (ZnO) flowers. The combination of experimental analysis and theoretical simulations demonstrated that small pores of the branching fiber network enhanced the interfacial interaction between ZnO flowers and cellulose fibers, thereby improving mechanical properties and optimizing flower structure. The interaction energy and electron density difference (EDD) simulation results demonstrated that the ZnO/cellulose interface structure shares significant attraction and charge transfer. Cellulose fibers ground for 20 cycles (CFG20) possessed dense branching fiber network and loaded with the smallest ZnO flowers, achieving a balance of strong mechanical properties and reaction efficiency. Remarkably, ZnO/CFG20 paper-based catalyst indicated strong photodegradation efficiency (100% for methyl orange, 100% for phenol, and 85.23% for aniline) and excellent reusability. This work will pave the way for the green regulation of catalysts. [ABSTRACT FROM AUTHOR]

Paper-based substrates containing dendrimer-stabilized Au:Ag:PAMAM nanoalloys for the SERS probing of the pesticide thiram in an aqueous solution. [Display omitted] Research on paper substrates prepared by inkjet deposition of metal nanoparticles for sensing applications has become a hot topic in recent years; however, the design of such substrates based on the deposition of alloy nanoparticles remains less explored. Herein, we report for the first time the inkjet printing of dendrimer-stabilized colloidal metal nanoalloys for the preparation of paper substrates for surface-enhanced Raman scattering (SERS) spectroscopy. To this end, nanoassemblies containing variable molar ratios of Au:Ag were prepared in the presence of poly(amidoamine) dendrimer (PAMAM), resulting in plasmonic properties that depend on the chemical composition of the final materials. The dendrimer-stabilized Au:Ag:PAMAM colloids exhibit high colloidal stability, making them suitable for the preparation of inks for long-term use in inkjet printing of paper substrates. Moreover, the pre-treatment of paper with a polystyrene (PS) aqueous emulsion resulted in hydrophobic substrates with improved SERS sensitivity, as illustrated in the analytical detection of tetramethylthiuram disulfide (thiram pesticide) dissolved in aqueous solutions. We suggest that the interactions established between the two polymers (PAMAM and PS) in an interface region over the cellulosic fibres, resulted in more exposed metallic surfaces for the adsorption of the analyte molecules. The resulting hydrophobic substrates show long-term plasmonic stability with high SERS signal retention for at least ninety days. [ABSTRACT FROM AUTHOR]

[Display omitted] Although transition metal metaphosphates (TMPOs) display special physical/chemical features and high theoretical capacities, their applications for supercapacitors (SCs) are still restricted by their low energy densities and inferior cycling stability. Herein, a novel strategy has been proposed to address these issues through in situ construction of cobalt nickle metaphosphate (Co 0.2 Ni 0.8 (PO 3) 2)@nickel diselenide (NiSe 2) core–shell heterostructure on carbon paper (CP) as a self-supporting flexible electrode for SCs. Particularly, this unique mushroom-like porous nanoarchitecture assembled by one-dimensional (1D) Co 0.2 Ni 0.8 (PO 3) 2 nanorods and zero-dimensional (0D) NiSe 2 nanospheres can expose abundant active sites and afford multi-dimensional channels, which favors rapid electron ions/electron transfer, accelerates the reaction kinetics, and alleviates volume changes during charging/discharging processes. Profiting from its well-aligned 1D/0D nanostructure and strong synergistic effect between Co 0.2 Ni 0.8 (PO 3) 2 and NiSe 2 , the Co 0.2 Ni 0.8 (PO 3) 2 @NiSe 2 /CP electrode delivers a specific capacity of 219.4 mAh/g/0.414 mAh cm−2 at 1 A/g and good cycling stability with capacity retention of 90.7% after 5000 cycles, outperforming many previously reported TMPO-based electrodes in literature. Impressively, an asymmetric supercapacitor (ASC) device assembled with Co 0.2 Ni 0.8 (PO 3) 2 @NiSe 2 as cathode and porous carbon as anode achieves an energy density of 69.2 Wh kg−1 at 736.0 W kg−1 and maintains a capacity retention of 97.6% after 20,000 charge–discharge cycles. This work provides an efficient approach to design multi-dimensional hybrid nanomaterials for high-performance SCs. [ABSTRACT FROM AUTHOR]

[Display omitted] Preparing new fluorescent materials for individualized and customized anti-counterfeiting applications to meet needs from the rapid development of e-commerce is of great significance. This paper reports the preparation of dynamic color-changing fluorescent polymer nanoparticles (PNPs) by constructing a fluorescence resonance energy transfer (FRET) pair between aggregation-induced emission (AIE) structures and photochromic structures. At first, methyl methacrylate (MMA) was used as the main monomer and tetraphenylethylene (TPE, a typical AIE structure) modified methacrylate (TPE-MA) and photochromic spiropyran (SP) modified methacrylate (SP-MA) as minor monomers were copolymerized to obtain the ternary copolymer PMMA-TPE-SP. Then, two types of PNPs based on this terpolymer was prepared via the reprecipitation method, with and without the addition of an amphiphilic polymer as the surfactant. The photophysical study shows that the fluorescence color of PNPs dynamically changes from blue to light violet and finally to red under UV light irradiation, a process that can be reversed under visible light. The PNPs were alternately irradiated with UV light and visible light for 10 cycles, which proved their good photoswitching reproducibility. The PNPs prepared with addition of surfactant were found to have stronger fluorescence and better stability. Finally, the photochromic fluorescent inks were prepared based on these PNPs. Several anti-counterfeiting scenarios and modes were designed, exhibiting excellent photochromic behavior on cellulose paper, even after 120 days of long-term storage. With simple equipment, desirable anti-counterfeiting effects with dynamic fluorescence color changing was achieved. This study demonstrated a promising hard-to-imitate anti-counterfeiting encryption strategy, which can achieve multiple outputs with simple operation and can be personalized and customized as needed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Formulation of water/solvent-based invisible security inks for flexo/screen printing using synthesized FNH. • Photostable & rub resistant prints with difficult to replicate but easy to authenticate security features. • Rub-induced orangish yellow emission from fluorescent cyan prints when shined with 270–400 nm light. • Cyanish green fluorescence from both rubbed & unrubbed prints upon 420–480 nm illumination. • THF or NaOH/KOH sensitive & penetrating fluorescence from the printed & rear side. • Detailed ridge characteristics achieved using FNH to develop LFPs. Smart functional materials with captivating optical properties are of immense importance due to their versatile applicability in anticounterfeiting and forensic science. A fluorene-naphthalene Schiff base (FNH) that displays aggregation induced emission, mechanofluorochromism and excitation wavelength dependent fluorescence inherent to the pristine and ground samples is synthesized. Water/solvent-based invisible security inks for flexo/screen printing were formulated using FNH as a smart pigment to check the originality of documents/branded products etc. The prints with good photostability, adherence to substrate and rub resistance are invisible in daylight showcasing multiple non-destructive and destructive techniques to authenticate the document. The inked area on UV dull paper substrate exhibits a weak emission, which is observed by the forger under UVA light. However, the user can validate the authenticity of the document by rubbing the print with hard objects, especially using a metal coin or glass rod to perceive a human eye detectable intensification in the orange fluorescence under the same illumination source. The intensity of the orange fluorescence reverts to the original, which enables the reuse of the security document after originality check. Yet another nondestructive authentication method is to observe a cyan fluorescence from the print and orangish yellow fluorescence from the rubbed printed region when shined with a 270–400 nm light source, whereas a cyanish green fluorescence both from the unrubbed and rubbed regions of the print when illuminated with a visible light source ranging from 420 to 480 nm. An additional verification through a destructive technique is to perceive red and yellow fluorescence of the ink film upon contact with THF and NaOH/KOH, respectively and a penetrating red fluorescence from the rear side of the THF-exposed printed area of the paper. The multi-level security features that cannot be easily replicated by the forger but allows a simple and easy validation process by the user are unique to FNH, used as a single pigment in the inks. Further, the applicability of the ground FNH in forensic science is established to distinctly observe Level I to II details of latent fingerprints. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of 2D Co x Ni y -MOF were synthesized by ultrasonic method. • Ti 3 C 2 T x nanosheets converting the OER process to a reaction-limited one. • 2D Co2NiMOF/MXene were prepared by electrostatically directed assembly. • The MOF/MXene interface allows for the rapid electron and ion transfer. • Benefiting from thin 2D/2D heterostructure, exhibit enhanced OER performance. Hydrogen production from water electrolysis is severely restricted by the poor reaction kinetics of oxygen evolution reaction (OER). In this work, a series of two-dimensional (2D) composites MOF/Ti 3 C 2 T x (the MXene phase) were fabricated by electrostatically directed assembly and used as catalysts for OER. The obtained composite materials exhibit enhanced electrocatalytic properties, thanks to the ultrathin 2D/2D heterostructure with abundant active sites in Co2Ni-MOF and the high electronic conductivity of Ti 3 C 2 T x. Among all the catalysts, Co2Ni-MOF@MX-1 achieved the best oxygen evolution performance with the lowest Tafel slope (51.7 mV dec−1) and the lowest overpotential (265 mV on carbon paper) at the current density of 10 mA cm−2. These results demonstrated that the synthesis of 2D composite materials by electrostatically directed assembly could be a feasible and promising method for the preparation of 2D heterostructure catalysts. [ABSTRACT FROM AUTHOR]

A novel cobalt-free, high-nickel cathode material, named 0.01B-LiNi 0.98 Mg 0.01 Zr 0.01 O 2 (NMZB), is introduced, aimed at enhancing stability. Mg, Zr, and B elements are strategically incorporated, with Mg and Zr primarily located inside particles and B predominantly on the surface, boosting both bulk and surface stability. NMZB exhibits outstanding electrochemical performance, with 90.5% capacity retention after 200 cycles at a 1C rate. This composition offers a pathway for cost-effective, high-performance lithium-ion battery technology. [Display omitted] Cobalt-free, high-nickel cathode materials are essential for the sustainable evolution of energy storage technologies, reducing the dependence on resources with significant environmental and social implications and simultaneously improving the efficiency and cost effectiveness of batteries. This paper introduces a cobalt-free, high-nickel cathode material called 0.01B-LiNi 0.98 Mg 0.01 Zr 0.01 O 2 (NMZB) developed using a novel blend of elements to enhance mechanical and surface chemical stability. Detailed evaluations confirmed the successful integration of Mg, Zr, and B into the particles, with Mg and Zr primarily located within the particle interior and B predominantly on the surface. This unique elemental configuration significantly improves the stability of the bulk phase and surface structure of the material. In addition, the refinement of primary particles within NMZB further enhances its mechanical stability. As a result, NMZB exhibits exceptional electrochemical stability, achieving 90.5 % capacity retention after 200 cycles at a 1C rate. This compositional strategy incorporates a high nickel content into layered materials while eliminating cobalt, which is crucial for advancing the development of cost effective and high-performance lithium-ion battery technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel ZnO/Bi 3 Ti 2 O 8 F:Yb3+, Er3+ Z-scheme heterojunction was synthesized. • The IEF of ZnO/BTOFYE heterojunction improves the carrier separation efficiency. • The IEF of ZnO/BTOFYE heterojunction improves the UC luminescence intensity. • ZnO/BTOFYE showed better photocatalytic degradation efficiency than BTOFYE. Exploring strategies to improve the near-infrared response of photocatalysts is an urgent challenge that can be overcome by utilizing upconversion (UC) luminescence to enhance photocatalysis. This paper reports the fabrication of a ZnO/Bi 3 Ti 2 O 8 F:Yb3+, Er3+ (ZnO/BTOFYE) Z-scheme heterojunction based on a Bi 3 Ti 2 O 8 F:Yb3+, Er3+ (BTOFYE) UC photocatalyst via electrostatic self-assembly. Fermi energy difference at the interface of BTOFYE and ZnO generates a strong internal electric field (IEF) in the Z-scheme heterojunction, offering a novel charge transfer mode that promotes carrier transfer and separation while retaining the strong redox capability. These results are confirmed through in situ X-ray photoelectron spectroscopy, in situ Kelvin probe force microscopy, electron spin resonance, and density functional theory calculations. In addition, the effect of the IEF on the UC luminescence process of Er3+ enhances the luminescence intensity, considerably improving the UC utilization efficiency. The optimal ZnO/BTOFYE degrades 64 % of ciprofloxacin in 120 min, which is 2.3 times more than that degraded by BTOFYE. Overall, the results of this study offer a reference for the rational development of high efficiency UC photocatalysts by generating IEF in Z-scheme heterojunctions. [ABSTRACT FROM AUTHOR]

[Display omitted] This paper develops a new measurement method to answer the question: How does one measure the interfacial tension of adsorbed droplets? This measurement is based on the placement of a bubble at a water|organic interface. To prove the concept, a bubble was formed by pipetting gas below the water|1,2-dichloroethane interface. Our values agree well with previous reports. We then extended the measurement modality to a more difficult system: quantifying interfacial tension of 1,2-dichloroethane droplets adsorbed onto conductors. Carbon dioxide was generated in the aqueous phase from the electro-oxidation of oxalate. Given carbon dioxide's solubility in 1,2-dichloroethane, it partitions, a bubble nucleates, and the bubble can be seen by microscopy when driving the simultaneous oxidation of tris(bipyridine)ruthenium (II), a molecule that will interact with CO 2 .−. and provide light through electrochemiluminescence. We can quantify the interfacial tension of adsorbed droplets, a measurement very difficult performed with more usual techniques, by tracking the growth of the bubble and quantifying the bubble size at the time the bubble breaks through the aqueous|1,2-dichloroethane interface. We found that the interfacial tension of nanoliter 1,2-dichloroethane droplets adsorbed to an electrified interface in water, which was previously immeasurable with current techniques, was one order of magnitude less than the bulk system. [ABSTRACT FROM AUTHOR]

[Display omitted] The present paper reports the fabrication of novel types of hybrid fibrous photocatalysts by combining block copolymer (BCP) templating, sol–gel processing, and coaxial electrospinning techniques. Coaxial electrospinning produces core–shell nanofibers (NFs), which are converted into hollow porous TiO 2 NFs using an oxidative calcination step. Hybrid BCP micelles comprising a single plasmonic nanoparticle (NP) in their core and thereof derived silica-coated core–shell particles are utilized as precursors to generate yolk-shell type particulate inclusions in photocatalytically active NFs. The catalytic and photocatalytic activity of calcined NFs comprising different types of yolk-shell particles is systematically investigated and compared. Interestingly, calcined NFs comprising silica-coated yolk-shells demonstrate enhanced catalytic and photocatalytic performance despite the presence of silica shell separating plasmonic NP from the TiO 2 matrix. Electromagnetic simulations indicate that this enhancement is caused by a localized surface plasmon resonance and a confinement effect in silica-coated yolk-shells embedded in porous TiO 2 NFs. Utilization of the coaxially electrospun TiO 2 NFs in combination with yolk-shells comprising plasmonic NPs reveals to be a potent method for the photocatalytic decomposition of numerous pollutants. It is worth noting that this study stands as the first occurrence of combining yolk-shells (Au@void@SiO 2) with porous electrospun NFs (TiO 2) for photocatalytic purposes and gaining an understanding of plasmon and confinement effects for photocatalytic performance. This approach represents a promising route for fabricating highly active and up-scalable fibrous photocatalytic systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The catalytic ozonation performances for seven CeO 2 catalysts with different morphologies and exposed facets are disclosed. • CeO 2 nanorods with (1 1 0) and (1 0 0) facets exposed show the best performance. • A linear relationship between Frenkel-type OV density and O 3 decomposition rate is revealed regardless of morphology and exposed facet. • DFT calculation and experimental data reveal OV boosts O 3 activation on both the Ce and hydroxyl sites of CeO 2. Morphology and facet effects of metal oxides in heterogeneous catalytic ozonation (HCO) are attracting increasing interests. In this paper, the different HCO performances for degradation and mineralization of phenol of seven ceria (CeO 2) catalysts, including four with different morphologies (nanorod, nanocube, nanooctahedron and nanopolyhedron) and three with the same nanorod morphology but different exposed facets, are comparatively studied. CeO 2 nanorods with (1 1 0) and (1 0 0) facets exposed show the best performance, much better than that of single ozonation, while CeO 2 nanocubes and nanooctahedra show performances close to single ozonation. The underlying reason for their different HCO performances is revealed using various experimental and density functional theory (DFT) calculation results and the possible catalytic reaction mechanism is proposed. The oxygen vacancy (OV) is found to be pivotal for the HCO performance of the different CeO 2 catalysts regardless of their morphology or exposed facet. A linear correlation is discerned between the rate of catalytic decomposition of dissolved ozone (O 3) and the density of Frenkel-type OV. DFT calculations and in-situ spectroscopic studies ascertain that the existence of OV can boost O 3 activation on both the hydroxyl (OH) and Ce sites of CeO 2. Conversely, various facets without OV exhibit similar O 3 adsorption energies. The OH group plays an important role in activating O 3 to produce hydroxyl radical (∙OH) for improved mineralization. This work may offer valuable insights for designing Facet- and OV-regulated catalysts in HCO for the abatement of refractory organic pollutants. [ABSTRACT FROM AUTHOR]

The present research utilizes the simple "plug-and-play" strategy to effectively impart layered rare-earth hydroxides with remarkable sensitivity, selectivity, and rapid fluorescence sensing detection ability towards nitroaromatic compounds, employing the excited-state proton transfer fluorescence quenching mechanism. This opens new possibilities for the efficient and accurate detection of toxic and hazardous nitroaromatic compounds and effectively protecting environmental health and public safety. [Display omitted] Convenient, rapid, and accurate detection of nitroaromatic organic toxins and harmful substances is of great significance in research. In the present study, two-dimensional layered rare-earth hydroxides (LYH) were used as ion-exchange matrix materials, and the anionic fluorescent dye molecules (HPTS) were successfully introduced into the LYH structures in situ via a simple and effective "plug-and-play" strategy, which gave the compounds ultra-sensitive fluorescence sensing detection of nitrobenzene, p-nitrotoluene and p-nitrophenol (Fluorescence response time < 1 sec , and the LOD for nitrobenzene, p-nitrophenol and p-nitrotoluene reached an impressive 349 ppb, 22 ppb and 98 ppb, respectively). Combined with theoretical calculations, we elucidated in detail the fluorescence quenching response mechanism of the LYH-HPTS towards nitroaromatic. Additionally, we also constructed fluorescent paper sensor, which effectively transformed the LYH-HPTS from theoretical detection to device application. The LYH-HPTS material is not only simple to synthesize, cost-effective and stable, but also has the features of fast response, excellent sensitivity and selectivity, and good reproducibility, which provides a new approach for the rapid and accurate detection of nitroaromatic. [ABSTRACT FROM AUTHOR]

[Display omitted] At the interface between an ion-exchange membrane and a multi-electrolyte solution, charged species redistribute themselves to minimize the free energy of the system. In this paper, we explore the Donnan equilibrium of membranes with quaternary electrolyte (Na+/Mg2+/K+/Ca2+/Cl−) solutions, experimentally. The data was used to calculate the ion activity coefficients for six commercial cation-exchange membranes (CEMs). After setting one of the activity coefficients to an arbitrary value, we used the remaining (N-1) activity coefficients as fitting parameters to describe the equilibrium concentrations of (N) ionic species with a mean relative error of 3 %. At increasing solution ionic strengths, the equivalent ion fractions of monovalent counter-ions inside the membrane increased at the expense of the multivalent ones in alignment with the Donnan equilibrium theory. The fitted activity coefficients were employed in a transport model that simulated a Donnan dialysis experiment involving all four cations simultaneously. The arbitrary value assigned to one activity coefficient affects the calculated Donnan potential at the membrane interface. Nevertheless, this arbitrary value does not affect the prediction of the ion concentrations inside the membrane and consequently does not affect the modeled ion fluxes. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: In the interfacial wetting boundary, the superhydrophobic surface is often damaged, and the anisotropic wettability of its surface has attracted many researchers' attention. The "petal effect" surface has typical anisotropic wettability. We predict that under the dual conditions of structural defects and high impact velocity, the "petal effect" becomes more adhesive on the surface. Experiments: This study refers to the droplet state on rose petals, structural defects were constructed on the superhydrophobic surface. This paper studies the influence of macro-structural defects on the wettability change from natural to bionic "lotus effect" to "petal effect" in both static and dynamic angles. Findings: Macro defects significantly change the static contact angle of the superhydrophobic surface. The higher the impact velocity of the droplet, the higher the energy dissipation of the "petal effect" surface (DSHS), which improves the adhesion of the surface to the droplet and prolongs the contact time. It is found that the defect structure and high impact velocity will directly affect the deposition and desorption of droplets on the superhydrophobic surface, and they are both essential. This wetting dynamic law is very likely to be helpful in the quantitative design of defect structure scale for dynamic desorption of droplets on superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] In this paper, microgels with uniform particle size were prepared by physically cross-linking the hydrophobically modified chitosan (h -CS) with sodium phytate (SP). The effects of cross-linking density on the interfacial adsorption kinetics, viscoelasticity, stress relaxation, and micorheological properties of the hydrophobically modified chitosan microgels (h -CSMs) at the oil–water interface were extensively investigated by the dilatational rheology, compressional rheology, and particle tracing microrheology. The results were correlated with the particle size, morphology, and elasticity of the microgels characterized by dynamic light scattering and atomic force microscopy. It was found that with the increase of cross-linking density, the h -CSMs changed from a polymer-like state to ultra-soft fussy spheres with higher elastic modulus. The compression isotherms demonstrated multi-stage increase caused by the interaction between the shells and that between the cores of the microgels successively. As the increase of cross-linking density, the h -CSMs diffused slower to the oil–water interface, but demonstrating faster permeation adsorption and rearrangement at the oil–water interface, finally forming interfacial layers of higher viscoelastic modulus due to the core-core interaction. Both the initial tension relaxation and the microgel rearrangement after interface expansion became faster as the microgel elasticity increased. The interfacial microrheology demonstrated dynamic caging effect caused by neighboring microgels. This article provides a more comprehensive understanding of the behaviors of polysaccharide microgels at the oil-water interface. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cryo-electron tomography was used to determine the structural characteristics of complicated surfactant aggregates. • Transitions branched WLMs → saturated network of WLMs → perforated vesicles were observed in solutions of zwitterionic and nonionic surfactants. • Transformations proceed through an increase in the number of branches at the expense of cylindrical subchains and semispherical endcaps. • Exponential distribution of subchains length was confirmed experimentally for multiconnected saturated networks. • Perforated vesicles were observed when the length of subchains became much shorter than the persistence length. The formation of micellar aggregates and the changes in their morphology are crucial for numerous practical applications of surfactants. However, a proper structural characterization of complicated micellar nanostructures remains a challenge. This paper demonstrates the advances of cryo-electron tomography (cryo-ET) in revealing the structural characteristics that accompany the evolution of surfactant aggregates. By using cryo-ET in combination with cryo-transmission electron microscopy (cryo-TEM), small-angle neutron scattering (SANS), and rheometry, studies were carried out on a model system composed of zwitterionic and nonionic surfactants. In this system, the molecular packing parameter was increased gradually by increasing the molar fraction of nonionic surfactant. A series of structural transformations was observed: linear wormlike micelles (WLMs) → branched WLMs → saturated network of multiconnected WLMs → perforated vesicles (stomatosomes). The transformations occur through an increase in the number of branches at the expense of cylindrical subchains and semispherical endcaps. Exponential distribution of subchains length was confirmed experimentally for multiconnected saturated networks. The stomatosomes were formed when the length of subchains becomes much shorter than the persistence length, causing the three-dimensional (3D) structure to transform into a two-dimensional (2D) membrane. This work identifies the mechanism of the structural changes, which can be further used to design various surfactant self-assemblies. [ABSTRACT FROM AUTHOR]

[Display omitted] Phase change materials (PCMs) can store and release latent heat under the designed phased change temperature and have received substantial interest for energy conservation and thermal control purposes. The use of PCMs in the construction of constant temperature buildings can improve the comfortable environment and save more energy. However, the leakage of PCMs during phase change process limits the application of PCMs. In this paper, a series of PCMs microcapsules with controllable core numbers is synthesized with paraffin (37 ℃) as the core and cross-linked chitosan as the wall. The single-core phase-change microcapsules (S−PCM) and multicore phase-change microcapsules (M−PCM) were prepared by adjusting the preparation condition. The latent heat of S−PCM and M−PCM are 61.4 mJ mg−1 and 50.1 mJ mg−1, respectively. The S-PCM and M−PCM display good stability without paraffin leakage. In addition, the composite blocks of gypsum and S−PCM (GSCM) and M−PCM (GMCM) were prepared and the thermoregulatory effection was investigated, where the surface temperature of GSCM was 5–10 ℃ lower than that of pure gypsum block. PCMs may also have broad application space in electronics, cold chain, and other industries. [ABSTRACT FROM AUTHOR]

This work vividly demonstrates the rational design of VSe 2-x O x -SS cathode as an effective strategy to achieve fast and highly aqueous zinc ion storage. [Display omitted] • A simple and fast surface oxygen implantation strategy was designed to adjust the electronic structure of VSe 2 and form a surface protective film. • The VSe 2-x O x -SS-30 electrode showed higher specific capacity, better rate performance and more satisfactory cycling stability. • The zinc (de)intercalation and transformation reactions mechanism was revealed by some ex-situ/in-situ techniques. Interfacial chemical modification is an effective strategy to adjust the strong Coulombic ion-lattice interactions with high valence cations experienced by electrode materials, facilitating the reaction kinetic. In this paper, a simple and fast surface oxygen implantation strategy was designed to adjust the electronic structure of stainless steel (SS) supported vanadium diselenide (VSe 2) nanosheets and form a surface protective film, which effectively accelerates the reaction kinetics of Zn2+ and extends the cycle life of the battery. It is demonstrated that the conductivity, pseudocapacitance and specific capacity can be tuned by selectively introducing oxygen species to the surface, which provides an important reference for the design of electrodes with controlled surface chemistry. Density functional theory (DFT) calculations also confirm that the electronic structure can be adjusted by surface oxygen injection strategy, which not only improves the conductivity, but also adjusts the adsorption energy, thus providing favorable conditions for zinc ion storage. Benefiting from the selenium vacancies and pores generated by the removal of part of selenium, and the oxide film formed on the surfaces, the VSe 2-x O x -SS-30 electrode showed higher specific capacity (188.4 mAh/g at 0.5 A g−1 after 50 cycles), better rate performance (107.1 mAh/g at 4 A g−1) and more satisfactory cycling stability (83.1 mAh/g at 5 A g−1 after 1800 cycles) than VSe 2 -SS electrode. Importantly, the flexible quasi-solid-state VSe 2-x O x -SS-30//Zn battery also exhibits high specific capacity and excellent environmental adaptability. Furthermore, the zinc (de)intercalation and transformation reactions mechanism was revealed by some ex-situ/in-situ techniques. [ABSTRACT FROM AUTHOR]

[Display omitted] As different monosaccharides exhibit different redox characteristics, this paper presented a novel colorimetric sensor array based on the glucose oxidase-like (GOx-like) activity of Au nanoparticles (NPs) for monosaccharides identification. AuNPs can use O 2 , ABTS+•, or [Ag(NH 3) 2 ]+ as an electron acceptor to catalyze the oxidation of monosaccharides in different velocity, resulting in cross-responsive signals. The current sensor array can distinguish between different monosaccharides or their mixtures through linear discriminant analysis (LDA) and hierarchical clustering analysis (HCA). Moreover, the glucose and fructose concentrations can be estimated simultaneously using a neural network regression model based on the sensor array. This method shows potential for monosaccharide detection in industrial, medical, and biological applications. [ABSTRACT FROM AUTHOR]

Crafting an inorganic semiconductor heterojunction with defect engineering and morphology modulation is a strategic approach to produce clean energy by the highly efficient light-driven splitting of water. In this paper, a novel Z-scheme sulfur-vacancy containing Zn 3 In 2 S 6 (Vs-Zn 3 In 2 S 6) nanosheets/In 2 O 3 hollow hexagonal prisms heterostructrue (Vs-ZIS6INO) was firstly constructed by an oil bath method, in which Vs-Zn 3 In 2 S 6 nanosheets grew on the surfaces of In 2 O 3 hollow hexagonal prisms to form a hollow core–shell structure. The obtained Vs-ZIS6INO heterostructrue exhibited much enhanced activity of the production of H 2 and H 2 O 2 by the light-driven water splitting. In particular, under visible light irradiation (λ > 420 nm), the rate of generation of H 2 of Vs-ZIS6INO sample containing 30 wt% Vs-Zn 3 In 2 S 6 (30Vs-ZIS6INO) could reach 3721 μmol g–1h−1, which was 87 and 6 times higher than those of Zn 3 In 2 S 6 (43 μmol g–1h−1) and Vs-Zn 3 In 2 S 6 (586 μmol g–1h−1), respectively. Meanwhile, 30Vs-ZIS6INO could exhibit the rate of H 2 O 2 production of 483 μmol g–1h−1 through the dual pathways of indirect 2e– oxygen reduction (ORR) and water oxidation (WOR) without adding any sacrifice agents, far exceeding In 2 O 3 (7 μmol g–1h−1) and Vs-Zn 3 In 2 S 6 (58 μmol g–1h−1). The excellent photocatalytic activities of H 2 and H 2 O 2 generations of Vs-ZIS6INO sample might result from the synergistic effect of the sulfur vacancy, hollow core–shell structure, and Z-scheme heterostructure, which accelerated the electron delocalization, enhanced the absorption and conversion of solar energy, reduced the carrier diffusion distance, and ensured high REDOX ability. In addition, the possible photocatalytic mechanisms for the production of H 2 and H 2 O 2 were discussed in detail. This study provided a new idea and reference for constructing the novel and efficient inorganic semiconductor heterostructures by coordinating vacancy defect and morphology design to adequately utilize water splitting for the production of clean energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Prepared ZIF-67/CoFe-LDH has excellent catalytic performance. • DFT demonstrated that oxygen vacancies mediated free radical and non-free radical pathways. • The role of reactive oxygen species in ZIF-67/CoFe-LDH/PMS system was studied. • The SMX degradation pathway was analyzed and the biotoxicity of the degradation intermediates was estimated. Herein, a novel rich oxygen vacancy (Ov) cobalt-iron hydrotalcite composite cobalt metal–organic framework material (ZIF-67/CoFe-LDH) was prepared by simple urea water and heat reduction approach and utilized for the peroxymonosulfate (PMS) system to remove sulfamethoxazole (SMX). 95 ± 1.32 % SMX (20 mg/L) was able to degraded in 20 min with TOC removal of 53 ± 1.56 % in ZIF-67/CoFe-LDH/PMS system. The system maintained a fantastic catalytic capability with wide pH range (3–9) and common interfering substances (Cl−, NO 3 −, CO 3 2−, PO 4 2− and humic acid (HA)), and the degradation efficiency could even remain 80.2 ± 1.48 % at the fifth cycle. Meanwhile, the applicability and feasibility of the catalysts for practical water treatment was verified by the degradation effects of SMX in different water environments and several other typical pollutants. Co and Fe bimetallic active centers synergistically activate PMS, and density functional theory (DFT) predicted adsorption energy about Ov in ZIF-67/CoFe-LDH for PMS was 1.335 eV, and O O bond length of PMS was stretched to 1.826 Å. As a result, PMS was more easily activated and broken, which accelerated the singlet oxygen (1O 2), sulfate radical (SO 4 •−), high-valent metals and other reactive oxygen species (ROS). Radical and non-radical jointly degrading the pollutants improved the catalytic effect. Finally, SMX degradation intermediates were analyzed to explain the degradation pathway and their biotoxicity was also evaluated. This paper provides a new research perspective of oxygen vacancy activating PMS to degrade pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] Component selection is crucial for microwave absorbents. Multi-component absorbers are increasingly useful and can be prepared through the rational design and control of various electrical, magnetic, and other auxiliary components. In this paper, Ni 3 Fe/NiFe 2 O 4 nanospheres with two-phase magnetism were designed for use as a multi-component absorber. Specifically, a Ni 3 Fe/ NiFe 2 O 4 @SPC composite with 3D networks was successfully fabricated by hydrothermal method, high-temperature carbonization for activation, and electrostatic self-assembly. The contact interface and coupling effect between the two magnetic components can promote the attenuation of electromagnetic waves. Moreover, the introduction of porous carbon successfully inhibits the easy aggregation of the magnetic particles. Impressively, with a filling load of 10 wt%, the optimal RL of the prepared Ni 3 Fe/NiFe 2 O 4 @SPC composite reaches −60.6 dB, and the effective absorption bandwidth is 5.2 GHz at 2 mm. The combination of two magnetic components and porous carbon in this multiphase microwave-absorbing composite demonstrates a feasible strategy for designing efficient microwave absorbers in the future. [ABSTRACT FROM AUTHOR]

Three-dimensional network structures of flower-like 1T/2H Molybdenum disulfide nanosheets anchored to carbon fibers were prepared, which exhibited satisfactory electromagnetic wave absorption properties, providing a path for the preparation of electromagnetic wave absorbing materials with wide effective absorption bandwidth. [Display omitted] • 3D 1T/2H MoS 2 /CNFs interconnected network structures were prepared; • Heterogeneous interfaces between CNFs and MoS 2 , 1T and 2H MoS 2 phase was built; • Excellent EM wave absorption with RL min of −42.26 dB and EAB of 6.48 GHz was obtained; • The EM wave absorption performance was proved by radar reflectance cross section simulation. With the wide application of electromagnetic waves in national defense, communication, navigation and home appliances, the electromagnetic pollution problem is becoming more and more prominent. Therefore, high-performance, and low-density composite wave-absorbing materials have attracted much attention. In this paper, three-dimensional (3D) network structures of flower-like 1T/2H Molybdenum disulfide nanosheets anchored to carbon fibers (1T/2H MoS 2 /CNFs) were prepared by electrostatic spinning technique and calcination process. The morphology and electromagnetic wave absorption properties were tuned by changing the content of flower-like MoS 2. The optimized 1T/2H MoS 2 /CNFs composite exhibits superior electromagnetic wave absorption with minimum reflection (RL min) of −42.26 dB and effective absorption bandwidth (EAB) of 6.48 GHz at 2.5 mm. Multi-facts contribute to the super performance. First, the uniquely designed nanosheet and 3D interconnected networks leads to multiple reflection and scattering of electromagnetic waves, which promotes the attenuation of electromagnetic waves. Second, the propriate content of CNFs and MoS 2 with different phase regulates its impedance matching characteristic. Third, Numerous heterogeneous interfaces existed between CNFs and MoS 2 , 1T and 2H MoS 2 phase results in interface polarization. Besides, the 1T/2H MoS 2 rich in defects induces defect polarization, improving the dielectric loss. Furthermore, the electromagnetic wave absorption performance was proved via radar reflectance cross section simulation. This work illustrates 1T/2H MoS 2 /CNFs is a promising material for electromagnetic absorption with wide bandwidth, strong absorption, low density, and high thermal stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Silica with hydrophobic hyperbranched structure was obtained. • Excellent defoaming and antifoaming effects were obtained in PDMS. • Hyperbranched microstructure exhibit superior "needle effect". • The "interface − coordination" defoaming mechanism is proposed. Hydrophobic nano silica powder is a kind of important synergist to silicone defoaming agents. The large pore volume and branched chain conformation of silica nanoparticles present superior effects on defoaming properties. However, silica nanoparticles synthesized by liquid phase easily aggregate and pore collapse because of their high surface activity and polarity, leading to poorer dispersity and limited practicability. In this paper, a novel hydrophobic silica with a hyperbranched structure was designed through in-situ modifying method with hexamethyldisilazane (HMDS) and polydimethylsiloxane (PDMS) in the liquid phase. The trimethylsilanol generated by HMDS hydrolysis reacts quickly with the highly active hydroxyl groups on the silica, causing the surface properties of the nanoparticles to transform from polar to non-polar properties. The steric hindrance of the trimethyl silicon and the reduction of the surface polarity effectively prevent silica pores from collapsing and maintain the macropore structures to realize the hyperbranched silica. At the same time, the −Si (CH 3) 2 − from PDMS endowed the hyperbranched silica with excellent hydrophobicity. When applied in the defoaming agent, the hydrophobicity of silica contributes to dewetting the foams, and the hyperbranched spatial structures play an enhanced needling effect. Therefore, this hydrophobic hyperbranched silica exhibited a surprising defoaming effect, which significantly reduced the defoaming time from 464.4 s to less than 2 s, superior to commercial defoaming silica (155.3 s). The defoaming efficiency reached 100 % within 2 s of the end of the shaking, and the defoamer antifoaming ability was improved to reach 27.5 min, which was 77 % higher than that of commercial defoamer. [ABSTRACT FROM AUTHOR]

[Display omitted] In this paper, we present a facile method of synthesis and modification of poly(glycidyl methacrylate) brushes with 6-aminofluorescein (6AF) molecules. Polymer brushes were obtained using surface-grafted atom transfer radical polymerization (SI-ATRP) and functionalized in the presence of triethylamine (TEA) acting both as a reaction catalyst and an agent preventing aggregation of chromophores. Atomic force microscopy (AFM), FTIR, X-ray photoelectron spectroscopy (XPS) were used to study the structure and formation of obtained photoactive platforms. UV-Vis absorption and emission spectroscopy and confocal microscopy were conducted to investigate photoactivity of chromophores within the macromolecular matrix. Owing to the simplicity of fabrication and good ordering of the chromophore in a thin nanometric layer, the proposed method may open new opportunities for obtaining light sensors, photovoltaic devices, or other light-harvesting systems. [ABSTRACT FROM AUTHOR]

According to the first principle, the SDS anions are preferentially adsorbed on the (0 0 2) surface of the Zn anode, forming a protective layer which prevents the adsorption of free water molecules and modifies the electrode/electrolyte interface. The SDS additive significantly inhibits the contact of water molecules with the interface, reduces the generation of by-products, and effectively prevents the growth of dendrites. Consequently, with the assistance of SDS additives, the Zn||Zn symmetrical battery sustains a long cycle life for 2000h. [Display omitted] Aqueous zinc-ion batteries are emerging as powerful candidates for large-scale energy storage, due to their inherent high safety and high theoretical capacity. However, the inevitable hydrogen evolution and side effects of the deposition process limit their lifespan, which requires rational engineering of the interface between anode and aqueous electrolyte. In this paper, an anionic surfactant as electrolyte additive, sodium dodecyl sulfonate (SDS), is introduced to deliver highly reversible zinc metal batteries. Unlike traditional surfactants, the solvation structure is not affected by SDS, which tends to adsorb on the (0 0 2) crystal plane of Zn with the purpose of effectively limiting the water molecules adsorption. Attributed to the natural hydrophobic part of SDS, a dynamic electrostatic shielding layer and a unique hydrophobic interface are constructed on the anode. Assisted by the above merits, the adverse surface corrosion, hydrogen evolution and dendrite growth are significantly inhibited without the sacrifice in the deposition kinetics of Zn ions. As a result, the Zn||Zn symmetric batteries demonstrate an increased cycle life of 2000 h (1 mA cm−2, 1 mA h cm−2) with the presence of SDS additive. Such strategy provides a new avenue for the developing advanced electrolytes to be applied in aqueous energy storage systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogel containing viologen-based hyperbranched polyamide amines with dual drug loading capacity. • Wearable Patch (Patch-DT) uses hydrogel as the drug-carrying cathode and magnesium flakes as the anode. • Patch-DT enables release of two drugs simultaneously, overcoming the limitations of monotherapy. • Visible drug monitoring through wearable Patch's electrochromic properties. Wearable drug delivery systems (DDS) have made significant advancements in the field of precision medicine, offering precise regulation of drug dosage, location, and timing. The performance qualities that wearable DDS has always strived for are simplicity, efficiency, and intelligence. This paper proposes a wearable dual-drug synergistic release patch. The patch is powered by a built-in magnesium battery and utilizes a hydrogel containing viologen-based hyperbranched polyamidoamine as both a cathode material and an integrated drug reservoir. This design allows for the simultaneous release of both dexamethasone and tannic acid, overcoming the limitations of monotherapy and ensuring effective synergy for on-demand therapy. In a mouse model with praziquimod-induced psoriasis, the patch demonstrated therapeutic efficacy at a low voltage. The inflammatory skin returned to normal after 5 days with the on-demand release of dual drugs. This work provides a promising treatment option considering its straightforward construction and the therapeutic advantages of dual-drug synergy. [ABSTRACT FROM AUTHOR]

[Display omitted] Silicon (Si) has gained substantial interest as a potential component of lithium-ion battery (LIB) anodes due to its high theoretical specific capacity. However, conventional methods for producing Si for anodes involve expensive metal reductants and stringent reducing environments. This paper describes the development of a calcium hydride (CaH 2)–aluminum chloride (AlCl 3) reduction system that was used for the in-situ low-temperature synthesis of a core–shell structured silicon–carbon (Si–C) material from rice husks (RHs), and the material was denoted RHs-Si@C. Moreover, as an LIB anode, RHs-Si@C exhibited exceptional cycling performance, exemplified by 90.63 % capacity retention at 5 A g−1 over 2000 cycles. Furthermore, the CaH 2 –AlCl 3 reduction system was employed to produce Si nanoparticles (Si NPs) from RHs (R-SiO 2 , where SiO 2 is silica) and from commercial silica (C-SiO 2). The R-SiO 2 -derived Si NPs exhibited a higher residual silicon oxides (SiO x) content than the C-SiO 2 -derived Si NPs. This was advantageous, as there was sufficient SiO x in the R-SiO 2 -derived Si NPs to mitigate the volumetric expansion typically associated with Si NPs, resulting in enhanced cycling performance. Impressively, Si NPs were fabricated on a kilogram scale from C-SiO 2 in a yield of 82 %, underscoring the scalability of the low-temperature reduction technique. [ABSTRACT FROM AUTHOR]

[Display omitted] The triboelectric nanogenerator (TENG) of natural biomaterials is a new type of energy harvesting device and can be used as a self-powered sensor, which has received extensive research and attention. In this paper, based on the biocompatibility of chitosan and chondroitin sulfate, ZnO-modified chitosan/chondroitin sulfate/ZnO TENG was prepared for research on wearable devices and sustainable power supply devices. This study employs molecular dynamics to compute the interaction energy between chitosan and ZnO molecules. Theoretical calculations have unequivocally substantiated the occurrence of a binding interaction between these two molecular entities. The effect of ZnO on chitosan/chondroitin sulfate morphology was investigated by atomic force microscopy. The chitosan/chondroitin sulfate/ZnO TENG has high flexibility and electrical output performance. It can reach 105 V and 3.3 µA of open-circuit voltage and short-circuit current. Chitosan/chondroitin Sulfate/ZnO TENG successfully converts the mechanical energy of human motion into electrical energy. Strong electrical signals are exhibited when making fists and waving fingers and wrists. The TENG is a self-powered source and lights up 70 blue light-emitting diodes (LEDs). The chitosan/chondroitin sulfate/ZnO TENG has demonstrated its capabilities in energy harvesting and wearable self-powered sensors. [ABSTRACT FROM AUTHOR]

[Display omitted] Supercapacitors have the advantages of fast charging and discharging speeds, high power density, long cycle life, and wide operating temperature range. They are widely used in portable electronic equipment, rail transit, industry, military, aerospace, and other fields. The design and preparation of low-cost, high-performance electrode materials still pose a bottleneck that hinders the development of supercapacitors. In this paper, coal was used as the raw material, and the coal-based porous carbon electrode material was constructed using the iodine intercalation-assisted activation method and used for supercapacitors. The CK-700 electrode exhibits excellent charge storage performance in a 6 M potassium hydroxide (KOH) electrolyte, with a maximum specific capacitance of 350 F/g at a current density of 0.5 A/g. In addition, it has an excellent rate performance (310 F/g at 1 A/g) and cycle stability (capacitance retention up to 91.7 % after 30000 cycles). This work provides a method for realizing high-quality, high-yield and low-cost preparation of coal-based porous carbon, and an idea for improving the performance of supercapacitors. [ABSTRACT FROM AUTHOR]

The design of multicomponent electrode materials is attractive for advanced supercapacitors due to synergistic and multifunctional effects among different active materials. We reported here a structure-designed synthesis strategy to controllably fabricate hierarchical NiCo 2 O 4 @NiO composites on carbon fiber paper. The hierarchical structure with NiCo 2 O 4 core and NiO shell provided more active sites for ion transportation and storage to improve utilization rate of electrode materials, enhancing the specific capacitance and rate performance. As an ideal electrode material for supercapacitors, the NiCo 2 O 4 @NiO electrode exhibit high specific capacitance (1188 F/g at 2 A/g), excellent rate capability with ∼85% capacitance retained at 10 A/g, and compelling cycling performance (∼106.8% of the initial capacitance retention over 7000 cycles). The present work demonstrated a structure-designed strategy to construct high-performance multicomponent electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Previous experimental work has shown that microcapsule walls, made by solidification of a molten wax, are unexpectedly permeable. The hypothesis was that this was due more to the structure of the wall than the material itself. The permeability of thin (sub and low micron thickness) natural waxes was measured where a membrane was placed between two cells and the diffusion of a dye (fluorescein) measured. A filter paper was used to support the membranes. Two methods were used to coat the filter paper; simple dipping and spin coating. The resulting surfaces were examined using SEM, XRD and contact angle. Results indicate that the permeability of very thin walled capsules can be investigated by forming a layer on a porous support and measuring diffusion rates. Both the composition of the wax and the sample preparation is extremely important to the structure and resulting permeability of the membranes. Spin coating was much more effective than dip coating in reducing permeability. Carnauba wax had a much lower permeability than beeswax. A difference in levels between the two cells was observed, indicating a potential Osmotic pressure difference at play which should be further investigated. [ABSTRACT FROM AUTHOR]

In this paper, Fe-N 3 S 1 and FeS sub-nano cluster are innovatively connected to S, N co-doped carbon matrix (SNC) by controlled calcination process. The local electron configuration of Fe center is modulated by this unique structure. Based on this design, Fe-N 3 S 1 and FeS sub-nano cluster shown excellent synergistic effects in oxygen reduction reaction. The optimized ORR activity was obtained. [Display omitted] Single atomic Fe-N 4 catalyst exhibits a great prospect for oxygen reduction reaction (ORR) and adjusting the intrinsic coordination structure and the carbon matrix structure effectively improves the catalytic activity. However, controlling the active site coordination structure and its surrounding environment at atomic level remains a challenge. In this paper, Fe-N 3 S 1 and FeS sub-nano cluster were innovatively concatenated on S, N co-doped carbon matrix (SNC), denoted as FeS/FeSA@SNC catalysts, for modulating ORR catalysis performance. Both experimental measurements and theoretical calculations have confirmed that the local electron configuration of Fe center is modulated by this unique structure combination leading to optimized ORR kinetics. Based on this design, the synthesized FeS/FeSA@SNC delivers ORR activity with a half-wave potential of 0.9 V (vs. RHE), excelling that of commercial Pt/C (0.87 V) and the Zn-air battery (ZAB) with this cathode catalyst delivers a peak power density of 126 mW cm−2. This work presents a novel strategy for manipulating the single-atom active sites through control the local coordination structure and provides a reference for the development of novel efficient ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] Development of new anti-counterfeiting technology to increase the difficulty of imitation and decoding is becoming increasingly important, but still remains challenging yet. In this work, we report the design of new fluorescence photoswitches based on photochromic tungsten oxide quantum dots (WO 3 QDs) for dual-mode anti-counterfeiting applications. Complexing photochromic WO 3 QDs with fluorescent gold nanoclusters (AuNCs) enables the construction of a photoswitchable fluorescence system (WO 3 -AuNCs) based on fluorescence resonance energy transfer. Detailed spectral and photophysical characterization showed that WO 3 QDs well-retain the photochromic properties within the WO 3 -AuNCs composite. Importantly, photoresponsive and highly reversible switching of both color and fluorescence signals was successfully achieved by simply alternating the irradiation with UV and visible light. Potential utility of photoswitchable WO 3 -AuNCs composite as novel dual-mode anti-counterfeiting materials has been successfully demonstrated, including photoswitchable ink, rewritable paper and number encryption. Compared with other anti-counterfeiting materials, the present photochromic WO 3 QDs-based fluorescent switches are easily synthesized and handled, and they can provide dual security mode (color and fluorescence). This work provides a generable WO 3 QDs-assisted strategy of fabricating advanced fluorescence photoswitches for versatile optical counterfeiting applications. [ABSTRACT FROM AUTHOR]

A serious of composites (SiW 9 M 3 @MIL-101(Cr) (M = Fe, Co, V, Mo) and D-SiW 9 Mo 3 @MIL-101(Cr), D, Disordered) were obtained by regulating transition metal composition and arrangement in the POMs. The structural characterization of composites reveals that the increase of electron cloud density of W atom in composites is the key to improve the photocatalytic performance. In this paper, the microchemical environment of POMs (as a catalytic active center) was regulated by transition metal doping method, thereby promoting the efficiency of photocatalytic ammonia synthesis for the composites, which provides new insights into the design of POM-based photocatalysts with high catalytic activity. [Display omitted] • The PNR performance of POMs@MIL-101(Cr) was studied by regulating transition metal compositions and arrangement in the POMs. • It is proposed for the first time that increasing the electron cloud density of W in POMs can promote the PNR reaction. • This work provides new insights into the design of POMs-based photocatalysts with high catalytic activity. The polyoxometalates (POMs) have been shown to be highly effective as reactive sites for photocatalytic nitrogen fixation reactions. However, the effect of POMs regulation on catalytic performance has not been reported yet. Herein, a series of composites (SiW 9 M 3 @MIL-101(Cr) (M = Fe, Co, V, Mo) and D-SiW 9 Mo 3 @MIL-101(Cr), D, Disordered) were obtained by regulating transition metal compositions and arrangement in the POMs. The ammonia production rate of SiW 9 Mo 3 @MIL-101(Cr) is much higher than that of other composites, reaching 185.67 μmol·h−1·g-1 cat in N 2 without sacrificial agents. The structural characterization of composites reveals that the increase of the electron cloud density of W atom in composites is the key to improve the photocatalytic performance. In this paper, the microchemical environment of POMs was regulated by transition metal doping method, thereby promoting the efficiency of photocatalytic ammonia synthesis for the composites, which provides new insights into the design of POM-based photocatalysts with high catalytic activity. [ABSTRACT FROM AUTHOR]

A novel electrochemical activation method was used to convert Bi(OH) 3 into α-Bi 2 O 3 with abundant oxygen vacancies. This material has a high specific capacitance and more persistent cycling stability than δ-Bi 2 O 3.When assembled into a hybrid supercapacitor, it shows an energy density of up to 114.9 Wh kg−1. [Display omitted] Bi 2 O 3 is an outstanding electrode material due to its high theoretical specific capacity. Hence, the synthesis of δ-Bi 2 O 3 materials with high oxygen-vacancy contents could improve their electrochemical performances but causes easy conversion to α-Bi 2 O 3 with low oxygen-vacancy contents, leading to poor cycling stability and limited practical applications. To overcome these problems, an effective strategy for constructing high oxygen vacancies α-Bi 2 O 3 on activated carbon fiber paper (ACFP) is developed in this study. To this end, ACFP/Bi(OH) 3 is first synthesized by the solvothermal method and then converted to ACFP/α-Bi 2 O 3 by in situ electrochemical activation. The proposed innovative electrochemical method quickly and easily introduces oxygen vacancies while preserving the three-dimensional structure, thereby promoting the charge transfer and ions diffusion in ACFP/α-Bi 2 O 3. Consequently, the specific capacity of ACFP/α-Bi 2 O 3 reaches 906C g−1 at 1 A g−1, and the capacity retention remains above 70% after 3000 cycles, a value higher than that of δ-Bi 2 O 3 (45%). Furthermore, the hybrid supercapacitor device assembled by ACFP/α-Bi 2 O 3 delivers a maximum energy density of 114.9 Wh kg−1 at 900 W kg−1 and outstanding cycle stability with 73.56 % retention after 5500 cycles. In sum, the proposed ACFP/α-Bi 2 O 3 with high performance and good stability looks promising for use as bismuth-based anode materials in supercapacitors and aqueous batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Silicon is considered as the next-generation anode material for lithium-ion batteries due to its high theoretical specific capacity and abundant crustal abundance. However, its poor electrical conductivity results in slow diffusion of lithium ions during battery operation. Simultaneously, the alloying process of silicon undergoes a 300 % volume change, leading to structural fractures in silicon during the cycling process. As a result, it loses contact with the current collector, continuously exposing active sites, and forming a sustained solid electrolyte interface (SEI) membrane. This paper presents the design of a fluorine-ion-regulated yolk–shell carbon-silicon anode material, highlighting the following advantages: (a) Alleviating volume changes through the design of a yolk–shell structure, thereby maintaining material structural integrity during cycling. (b) Carbon shell prevents silicon from coming into contact with the electrolyte, simultaneously improving silicon's electrical conductivity and increasing ion/electron conductivity. (c) Utilizing fluorine-ion interface modification to obtain an SEI membrane rich in fluorine components (such as LiF), thereby enhancing its long cycling performance. The F-Si@Void@C exhibits outstanding electrochemical performance, with a reversible capacity of 1166 mAh/g after 900 cycles at a current density of 0.5 A/g. [ABSTRACT FROM AUTHOR]

This paper utilized the hydrothermal method and freeze-drying technology to prepare the macroscopic aerogel structure and powder structure of MOF-808/RGO. Through comparative analysis of aspects such as photocatalytic CO 2 reduction performance, electron transfer efficiency, macroscopic structure, and microstructure, it has been discovered that aerogel structure can provide favorable conditions for mass transfer of CO 2 and water molecules, and light propagation. The introduction of RGO successfully captures electrons and the reduction reaction occurs on the surface of the material. [Display omitted] • Macroscopic aerogel and powder structures of the MOF-808/RGO composite photocatalysts were fabricated separately and used for comparison. • The photocatalytic performance of the MOF-808/RGO macroscopic aerogels in reducing CO 2 to CO was approximately 16 times that of MOF-808 and 12 times that of RGO. • The aerogel structure provides an abundance of pore structures within the material. • The presence of the aerogel structure successfully enhanced the photothermal and photoelectric conversion efficiencies of the composite photocatalysts. Three-dimensional (3D) macroscopic aerogels have emerged as a critical component in the realm of photocatalysis. Maximizing the integration of materials can result in enhanced efficiency and selectivity in photocatalytic processes. In this investigation, we fabricated MOF-808/reduced graphene oxide (RGO) 3D macroscopic aerogel composite materials employing the techniques of hydrothermal synthesis and freeze-drying. The results revealed that the macroscopic aerogel material exhibited the highest performance in CO 2 reduction to CO, particularly when the concentration of RGO was maintained at 5 mg mL−1. In addition, we synthesized powder materials of MR-5 composite photocatalysts and conducted a comparative analysis in terms of photocatalytic CO 2 reduction performance and electron transfer efficiency. The results show that the macroscopic aerogel material boasts a high specific surface area, an abundant internal pore structure, and increased active sites. These attributes collectively enhance light energy utilization, and electron transfer rates, thereby, improving photothermal and photoelectric conversion efficiencies. Furthermore, we conducted in-situ FT-IR measurements and found that the M/R-5 aerogel exhibited the best CO 2 adsorption capacity under a CO 2 flow rate of 10 mL min−1. The density functional theory results demonstrate the correlation between the formation pathway of the product and the charge transfer pathway. This study provides useful ideas for realizing photocatalytic CO 2 reduction of macroscopic aerogel materials in gas–solid reaction mode. [ABSTRACT FROM AUTHOR]

[Display omitted] • In 2 O 3 quantum dots were successfully loaded on g-C 3 N 4 by pre-forming In–N bonds. • High-temperature oxidation can improve the oxygen adsorption capacity of g-C 3 N 4. • S-scheme transfer exhibits excellent photoelectric conversion efficiency. • Hydroperoxide C β intermediate was an important intermediate in lignin β–O–4 bond cleavage reaction. The graphitic carbon nitride (g-C 3 N 4) photocatalysis has emerged as a clean method for cleaving lignin-linked bonds due to its mild and sunlight-driven reaction conditions. The fast electron–hole pair complex of g-C 3 N 4 constrains its degradation efficiency, making the heterojunction construction a popular solution. The conventional methods of preparing g-C 3 N 4 heterojunctions by physical mixing destroy π-conjugations in g-C 3 N 4 , reducing the adsorption of lignin containing benzene rings. In this study, a novel indium oxide (In 2 O 3) quantum dot–g-C 3 N 4 0D/2D heterojunction was prepared through the high-temperature oxidation of pre-prepared indium-doped g-C 3 N 4. The introduction of In 2 O 3 at the quantum dot level minimizes the interference with lignin adsorption capacity. The strong combination of the two (In 2 O 3 and g-C 3 N 4) increases the intersection interface area, promoting the S-scheme transfer route of the photogenerated electrons. Consequently, this enhances the photoelectric conversion efficiency and carrier lifetime of the heterojunction, and inhibits the rapid recombination of photogenerated electron–hole pairs in g-C 3 N 4. The proposed heterojunction was 3 times more efficient than g-C 3 N 4 alone for selective cleavage of lignin β–O–4 bonds after 2 h of sunlight irradiation. Combined with inhibitor experiments and gas chromatography–mass spectrometry analysis, this paper defines the reactive oxides and proposes a cleavage pathway for the lignin β–O–4 bonds in In 2 O 3 –g-C 3 N 4 heterojunction system. [ABSTRACT FROM AUTHOR]

[Display omitted] Researchers are interested in single-atom catalysts with atomically scattered metals relishing the enhanced electrocatalytic activity for nitrogen reduction and 100 % metal atom utilization. In this paper, we investigated 18 transition metals (TM) spanning 3d to 5d series as efficient nitrogen reduction reaction (NRR) catalysts on defective 2D SiP V layered structures through first-principles calculation. A systematic screening identified Mo@SiP V , Nb@SiP V , Ta@SiP V and W@SiP V as superior, demonstrating enhanced ammonia synthesis with significantly lower limiting potentials (−0.25, −0.45, −0.49 and −0.15 V, respectively), compared to the benchmark −0.87 eV for the defective SiP. In addition, the descriptor Δ G *N was introduced to establish the relationship between the different NRR intermediates, and the volcano plot of the limiting potentials were determined for their potential-determining steps (PDS). Remarkably, the limiting voltage of the NRR possesses a good linear relationship with the active center TM atom Ɛ d , which is a reliable descriptor for predicting the limiting voltage. Furthermore, we verified the stability (using Ab Initio Molecular Dynamics − AIMD) and high selectivity (U L (NRR)- U L (HER) > -0.5 V) of these four catalysts in vacuum and solvent environments. This study systematically demonstrates the strong catalytic potential of 2D TM@SiP V (TM = Mo, Nb, Ta, W) single-atom catalysts for nitrogen reduction electrocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sc3+ is selected to replace V3+ and PAN is introduced to provide porous carbon substrate. • Sc bonds with oxygen to form ScO 6 , resulting in improved structural stability and kinetics. • PAN can induce a beneficial nitrogen-doped carbon skeleton with defects, resulting in enhanced electronic conductivity. • After cycling XRD/SEM confirms the stabilized porous carbon skeleton and improved crystal stability. • Ex-situ XRD analysis reveals the crystal volume change in Sc-3 is relatively slight but reversible. The poor structural stability and conductivity of Na 3 V 2 (PO 4) 3 (NVP) have been serious limitations to its development. In this paper, Sc3+ is selected to replace partial site of V3+ which can enhance its ability to bond with oxygen, forming the ScO 6 octahedral unit, resulting in improved structural stability and better kinetic properties for the NVP system. Moreover, due to the larger ionic radius of Sc3+ compared to V3+, moderate Sc3+ substitution can support the crystal framework as pillar ions and expand the migration channels for de-intercalation of Na+, thus efficiently promoting ionic conductivity. The introduction of polyacrylonitrile (PAN) to provide an N -doped porous carbon substrate is another key aspect. The low-cost carbon resource of PAN can induce a beneficial nitrogen-doped carbon skeleton with defects, enhancing electronic conductivity at the interface to reduce the polarization phenomenon. The established pore structure can serve as a buffer for unit cell deformation caused by Na+ migration. Furthermore, the enlarged specific surface area provides more active sites for electrolyte infiltration, improving the material utilization rate. The after cycling X-ray Diffraction/scanning electron microscope (XRD/SEM) further confirms the stabilized porous carbon skeleton and improved crystal stability of Sc-3 material. Ex-situ XRD analysis shows that the crystal volume change in the Sc-3 cathode is relatively slight but reversible during the charge/discharge process, indicating that Sc3+ doping plays a crucial role in stabilizing the unit cell structure. The hybrid Sc/VO 6 and PO 4 units jointly build a strong bone structure to resist stress and weaken deformation. Accordingly, the optimized Sc-3 sample reveals an initial capacity of 115.9 mAh/g at 0.1C, with a capacity retention of 78.6 % after 2000 cycles at 30C. The Sc-3//CHC full battery can release a capacity of 191.3 mAh/g at 0.05C, accompanied by successful illumination, showcasing its promising practical applications. [ABSTRACT FROM AUTHOR]

The cylindrical surface with Bragg-enhanced Fresnel reflectivity constructed from non-close-packed photonic crystals (NPCs) was designed for spectral selectivity and optical gain, which broke through the limitations of traditional Fresnel curved mirror with lowest central reflectivity and inability to perform spectral selectivity, and was conducive to expending the application of Fresnel mirror in the fields of signal transmission, optical measurement and instrument design. [Display omitted] According to the Fresnel theory, the reflectivity intensity of spherical and cylindrical convex surfaces decreases from their edge to center, and it is noteworthy and interesting for optical gain to study the enhancement of center reflectance. In this paper, a polydimethylsiloxane (PDMS) − encapsulated cylindrical non-closed-packed photonic crystals (NPCs) composite with Bragg-enhanced Fresnel reflectance was designed for spectral selectivity and optical gain. Theoretically and experimentally, the periodically ordered structure of NPCs achieved high-reflection of light in photonic bandgap and high-transmission in other bands, which enhanced Fresnel reflectivity of the convex center to specific bands. Furtherly, the cylindrical NPCs hydrogel with stretchability was applied for the dynamic tuning of optical signals. The reflection peak of the PDMS-encapsulated cylindrical NPCs composite blue-shifted from 608 nm to 413 nm with 50 % tensile strain and achieved a rapid transition of structural color from orange to blue-violet in 60 cycles. The new kind of photonic crystals composite for optical gain and spectral selection broke through the limitations of traditional Fresnel curved mirrors with the lowest central reflectivity and inability to perform spectral selectivity, and have great significance and application prospects in fields of signal transmission, optical measurement, and instrument design. [ABSTRACT FROM AUTHOR]

[Display omitted] • Room temperature and ultrafast synthesis of sulfur quantum dots (SQDs) is presented. • The conversion of elemental sulfur to fluorescent SQDs can be completed in 10 min. • The prepared SQDs have a photoluminescence quantum yield as high as 23.6%. • The utilization of SQDs to sensitively detect tetracycline and Ca2+ ions is reported. • A sensitive logic gate sensor based on SQDs is constructed. The direct and rapid conversion of abundant and cheap elemental sulfur into fluorescent sulfur quantum dots (SQDs) at room temperature is a critical and urgent challenge. Conventional synthesis methods require high temperatures, high pressures, or specific atmospheric conditions, making them complex and impractical for real applications. Herein, we propose a simple method for synthesizing SQDs simply by adding H 2 O 2 to an elemental sulfur-ethylenediamine (S-EDA) solution at room temperature. Remarkably, within a mere 10 min, SQDs with a photoluminescence quantum yield of 23.6 % can be obtained without the need for additional steps. A comprehensive analysis of the mechanism has demonstrated that H 2 O 2 is capable of converting S x 2− ions generated in the S-EDA solution into zero-valent sulfur atoms through oxidation. The obtained SQDs can be utilized as a fluorescent probe for detection of tetracycline (TC) and Ca2+ ions with the limit of detection (LOD) of 0.137 μM and 0.386 μM respectively. Moreover, we have developed a sensitive logic gate sensor based on SQDs, harnessing the activated cascade effect to create an intelligent probe for monitoring trace levels of TC and Ca2+ ions. This paper not only presents a viable approach for ultrafast and scalable synthesis of SQDs at room temperature, but also contributes to the efficient utilization of elemental sulfur resources. [ABSTRACT FROM AUTHOR]

In this paper, a CuSCN hole transport layer (HTL) is introduced between BiVO 4 and NiFeO x oxygen evolution cocatalyst (OEC) to form BiVO 4 /CuSCN/NiFeO x photoanode. Characterization and DFT calculations suggest that the high PEC performance is attributed to the incorporation of CuSCN as a HTL, which effectively facilitates charge transfer and accelerates the water oxidation kinetics, resulting in an enhanced PEC water splitting performance (5.65 mA cm−2 at 1.23 V vs. RHE). [Display omitted] • BiVO 4 /CuSCN/NiFeO x photoanode prepares by inserting CuSCN between BiVO 4 and NiFeO x. • The CuSCN promotes the transfer of holes from BiVO 4 to NiFeO x OEC. • The CuSCN exhibits enhanced OER activity and accelerates water oxidation kinetics. • BiVO 4 /CuSCN/NiFeO x photoanode achieves enhanced PEC water splitting performance. Modification of oxygen evolution co-catalyst (OEC) on the surface of bismuth vanadate (BiVO 4) can effectively improve the kinetics of water oxidation, but it is still limited by the small hole extraction driving force at the BiVO 4 /OEC interface. Modulating the BiVO 4 /OEC interface with a hole transfer layer (HTL) is expected to facilitate hole transport from BiVO 4 to the OEC surface. Herein, a copper(I) thiocyanate (CuSCN) HTL is inserted between BiVO 4 and NiFeO x OEC to create BiVO 4 /CuSCN/NiFeO x photoanode, resulting in a significant enhancement of photoelectrochemical (PEC) water splitting performance. From electrochemical analyses and density functional theory (DFT) simulations, the markedly enhanced PEC performance is attributed to the insertion of CuSCN as an HTL, which promotes the extraction of holes from BiVO 4 surface and boosts the water oxidation kinetics. The optimal photoanode achieves a photocurrent density of 5.6 mA cm−2 at 1.23 V versus the reversible hydrogen electrode (vs. RHE) and an impressive charge separation efficiency of 96.2 %. This work offers valuable insights into the development of advanced photoanodes for solar energy conversion and emphasizes the importance of selecting an appropriate HTL to mitigate recombination at the BiVO 4 /OEC interface. [ABSTRACT FROM AUTHOR]

[Display omitted] Engineering platinum-free catalysts for hydrogen evolution reaction (HER) with high activity and stability is essential for electrochemical hydrogen production. In this paper, we report the synthesis of cobalt-doped AlNi 3 /NiO (Co-AlNi 3 /NiO) electrode with three-dimensional nanoporous structure via chemical dealloying method. Density functional theory (DFT) calculations reveal that Co-AlNi 3 /NiO can accelerate water adsorption / dissociation and optimize adsorption–desorption energies of H* intermediates, thus improving the intrinsic HER activity. Both the introduction of Co and Al can efficiently ameliorate the electronic density around Ni sites of NiO and AlNi 3 , which can effectively reduce the energy barrier towards Volmer–Heyrovsky reaction and thus synergistically promote the hydrogen evolution. Benefiting from the large electrochemical active surface area, high electrical conductivity and electronic effect, the nanoporous Co-AlNi 3 /NiO catalyst exhibits remarkable HER activity with an overpotential of 73 mV at a current density of 10 mA cm−2 in alkaline condition, outperforming most of the reported non-precious metal catalysts. The nanoporous Co-AlNi 3 /NiO catalyst can operate continuously over 1000 h at high current densities with a robust stability. This work provides a new vision for the development of low-cost and efficient electrocatalysts for energy conversion applications. [ABSTRACT FROM AUTHOR]