Fast polydopamine coating on reverse osmosis membrane: Process investigation and membrane performance study.

We report a novel membrane surface modification method using a fast polydopamine coating (fPDAc) strategy. Specifically, NaIO was introduced in the coating process to accelerate the polydopamine deposition rate. Surface properties and separation performances of fPDAc-coated reverse osmosis membranes were characterized and compared to those obtained using the conventional slow polydopamine coating (sPDAc) strategy.

pH and Temperature Dual-Responsive Plasmonic Switches of Gold Nanoparticle Monolayer Film for Multiple Anticounterfeiting.

Two-dimensional (2D) gold nanoparticle (Au NP) monolayer film possesses a lot of fascinating peculiarities, and has shown promising applications in photoelectrical devices, catalysis, spectroscopy, sensors, and anticounterfeiting. Because of the localized surface plasmon resonance (LSPR) property predetermined by the natural structure of metal nanoparticles, it is usually difficult to realize the reversible LSPR transition of 2D film. In this work, we report on the fabrication of a large-area free-standing Au NP monolayer film with dual-responsive switchable plasmonic property using a pH- or thermal-responsive dendronized copolymer as a stimuli-sensitive linker.

Counterion-Induced Nanosheet-to-Nanofilament Transition of Lyotropic Bent-Core Liquid Crystals.

The smart flexibility of phase transitions in liquid crystals (LCs) makes them suitable for various applications and is an important research field in contemporary science, engineering, and technology. Unlike most reports focused on bent-core LCs in the thermotropic situation, in our present study, we designed and synthesized a fully rigid bent-core molecule with the sulfonic acid group replacing conventional flexible chains. A rich variety of counterion-induced supramolecular LC phase behaviors have been systematically investigated.

Polymerization driven monomer passage through monolayer chemical vapour deposition graphene.

Mass transport through graphene is receiving increasing attention due to the potential for molecular sieving. Experimental studies are mostly limited to the translocation of protons, ions, and water molecules, and results for larger molecules through graphene are rare. Here, we perform controlled radical polymerization with surface-anchored self-assembled initiator monolayer in a monomer solution with single-layer graphene separating the initiator from the monomer.

Enhanced electrochemical voltammetric fingerprints for plant taxonomic sensing.

Graphene-embedded plant tissues show a high sensitivity to electrochemical signals, which enables a screen-printed electrode to be used for electrochemical fingerprint recording. The electrochemical fingerprints obtained under different conditions can be transformed into multidimensional recognition modes for plant identification. These electrochemical fingerprints reflect the types and quantities of the electrochemically active substances in plant tissues such that the fingerprints can be used for chemotaxonomic investigations.

Self-Assembly of CoPt Magnetic Nanoparticle Arrays and its Underlying Forces.

Nanoparticles covered with surfactants are often used to study particle motion patterns and self-assembly processes in solutions. Surfactants have influence on the interparticle interactions and therefore on the particle motion tracks and final patterns. In this study, CoPt nanoparticles are synthesized in aqueous solution without any surfactant.

Facile metal-free reduction-based synthesis of pristine and cation-doped conductive mayenite.

In the present study we synthesized conductive nanoscale [CaAlO](4e) (hereafter denoted as CA:e) material, and reduced graphene oxide (rGO) was produced, which was unexpected; graphene oxide was removed after melting the sample. The conductivity of CA:e composites synthesized at 1550 °C was 1.25 S cm, and the electron concentration was 5.

Dialysis assisted ligand exchange on gold nanorods: Amplification of the performance of a lateral flow immunoassay for E. coli O157:H7.

Ligand exchange on the surface of gold nanorods (AuNRs) is widely used, but conventional methods usually require multiple centrifugation cycles to completely remove cetyltrimethylammonium bromide (CTAB). This can lead to undesired aggregation of AuNRs. A dialysis-assisted protocol is described here for ligand exchange on AuNRs.

A multiscale hydrothermal carbon layer modified carbon fiber for composite fabrication.

A novel multiscale hydrothermal carbon layer (MHTCL) for carbon fiber (CF) surface modification was developed. The MHTCL is a multiscale high-disorder amorphous carbon coating with a colored appearance, abundant functional groups, multiscale roughness, a large specific surface area, a high surface energy, and good wetting ability. The O/C atom ratios of the MHTCL-modified CF were in the range of 0.

Carbon coating and Al-doping to improve the electrochemistry of LiCoSiO polymorphs as cathode materials for lithium-ion batteries.

LiCoSiO has the potential for use as a high safety, high energy-density cathode material for lithium-ion batteries but suffers from bad electrochemical performance. Herein, we demonstrate a profound study on the effects of carbon coating and Al-doping on the electrochemistry of LiCoSiO synthesized by a two-step method. The synthesized 4 at% Al-doped LiCoSiO/C allows two lithium removals between 2.

The evolution of phase constitution and microstructure in iron-rich 2:17-type Sm-Co magnets with high magnetic performance.

Iron-rich 2:17-type Sm-Co magnets are important for their potential to achieve high coercivity and maximum magnetic energy product. But the evolution of phase structure, which determines magnetic properties, remains an unsolved issue. In this study, the phase constitution and microstructure of solution-treated 2:17-type Sm-Co alloys are studied.

Polyhedral perspectives on the capacity limit of cathode compounds for lithium-ion batteries: a case study for LiCoO.

Anionic redox revealed reversibility in Li-rich layered oxides Li2MO3, which was strongly dependent on transition metal element M and geometrical structures. This sheds new light on high energy lithium ion batteries, and also inspires the question whether super high capacity is achievable in lithium compounds with stoichiometry close to Li2O. The tetrahedron structured Li6CoO4 is one kind of oxides with extremely high Li stoichiometry.

Analysis of oxidation degree of graphite oxide and chemical structure of corresponding reduced graphite oxide by selecting different-sized original graphite.

The thermal exfoliation and reduction of graphite oxide (GO) is the most commonly used strategy for large-scale preparation of graphene, and the oxidation degree of GO would influence the chemical structure of prepared graphene, thereby affecting its final physical and chemical properties. In addition to serving as the precursor for synthesizing graphene, GO also possesses great potential for various important applications owing to its abundant oxygen-containing groups and hybrid electronic structure. Therefore, systematically studying the influencing factors on the oxidation degree of GO and clarifying the effect of oxidation degree on the corresponding graphene is particularly important.

Polyiodide-Shuttle Restricting Polymer Cathode for Rechargeable Lithium/Iodine Battery with Ultralong Cycle Life.

Rechargeable lithium/iodine (Li/I) batteries have attracted much attention because of their high gravimetric/volumetric energy densities, natural abundance and low cost. However, problems of the system, such as highly unstable iodine species under high temperature, their subsequent dissolution in electrolyte and continually reacting with lithium anode prevent the practical use of rechargeable Li/I cells. A polymer-iodine composite (polyvinylpyrrolidone-iodine) with high thermostability is employed as cathode material in rechargeable Li/I battery with an organic electrolyte.

Nanozyme-based lateral flow assay for the sensitive detection of Escherichia coli O157:H7 in milk.

Lateral flow assay (LFA) has been applied in many fields due to its relative ease of use and cost-effectiveness. However, it has low sensitivity and its applications are limited. Probe materials play a significant role in improving the detection efficiency and sensitivity of LFA.

Shape Memory Hydrogels with Simultaneously Switchable Fluorescence Behavior.

Realization of shape memory process in polymeric hydrogels at ambient condition is a significant development to shape memory materials. The sound understanding of the dynamic shape memory process is fundamentally important but limited. Here, a novel shape memory hydrogel with simultaneously switchable fluorescence behavior is developed.

Humidity-Responsive Gold Aerogel for Real-Time Monitoring of Human Breath.

Humidity sensors have received considerable attention in recent years because of their significance and wide applications in agriculture, industries, goods stores, and medical fields. However, the conventional humidity sensors usually possessed a complex sensing mechanism and low sensitivity and required a time-consuming, labor-intensive process. The exploration for an ideal sensing material to amplify the sensitivity of humidity sensors is still a big challenge.

Dopant-Free and Carrier-Selective Heterocontacts for Silicon Solar Cells: Recent Advances and Perspectives.

By combining the most successful heterojunctions (HJ) with interdigitated back contacts, crystalline silicon (c-Si) solar cells (SCs) have recently demonstrated a record efficiency of 26.6%. However, such SCs still introduce optical/electrical losses and technological issues due to parasitic absorption/Auger recombination inherent to the doped films and the complex process of integrating discrete p- and n-HJ contacts.

Direct Observation of Magnetocrystalline Anisotropy Tuning Magnetization Configurations in Uniaxial Magnetic Nanomaterials.

Discovering the effect of magnetic anisotropy on the magnetization configurations of magnetic nanomaterials is essential and significant for not only enriching the fundamental knowledge of magnetics but also facilitating the designs of desired magnetic nanostructures for diverse technological applications, such as data storage devices, spintronic devices, and magnetic nanosensors. Herein, we present a direct observation of magnetocrystalline anisotropy tuning magnetization configurations in uniaxial magnetic nanomaterials with hexagonal structure by means of three modeled samples. The magnetic configuration in polycrystalline BaFeO nanoslice is a curling structure, revealing that the effect of magnetocrystalline anisotropy in uniaxial magnetic nanomaterials can be broken by forming an amorphous structure or polycrystalline structure with tiny grains.

Opening Magnesium Storage Capability of Two-Dimensional MXene by Intercalation of Cationic Surfactant.

Two-dimensional (2D) TiC MXene has attracted great attention in electrochemical energy storage devices (supercapacitors and lithium-ion and sodium-ion batteries) due to its excellent electrical conductivity as well as high volumetric capacity. Nevertheless, a previous study showed that multivalent Mg ions cannot reversibly insert into MXene, resulting in a negligible capacity. Here, we demonstrate a simple strategy to achieve high magnesium storage capability for TiC MXene by preintercalating a cationic surfactant, cetyltrimethylammonium bromide (CTAB).

A Novel Anisotropic Hydrogel with Integrated Self-Deformation and Controllable Shape Memory Effect.

Although shape memory polymers have been highlighted widely and developed rapidly, it is still a challenging task to realize complex temporary shapes automatically in practical applications. Herein, a novel shape memory hydrogel with the ability of self-deformation is presented. Through constructing an anisotropic poly(acrylic acid)-polyacrylamide (PAAc-PAAm) structure, the obtained hydrogel exhibits stable self-deformation behavior in response to pH stimulus, and the shapes that formed automatically can be fixed by the coordination between carboxylic groups and Fe ; therefore, self-deformation and shape memory behaviors are integrated in one system.

The influence of on tin-coated copper in an aqueous environment.

The influence of Bacillus subtilis (BS) on tin-coated copper in an aqueous environment was investigated by exposing the sample to a culture medium inoculated with BS. Scanning electron microscopy, electrochemical measurements and chemical analyses were performed to study the corrosion mechanism. The experimental results show that BS can adhere and gather on the surface of the sample, resulting in oxygen consumption at the place where the bacteria are densely attached.

A Combined Self-Consistent Method to Estimate the Effective Properties of Polypropylene/Calcium Carbonate Composites.

In this work, trying to avoid difficulty of application due to the irregular filler shapes in experiments, self-consistent and differential self-consistent methods were combined to obtain a decoupled equation. The combined method suggests a tenor independent of filler-contents being an important connection between high and low filler-contents. On one hand, the constant parameter can be calculated by Eshelby's inclusion theory or the Mori⁻Tanaka method to predict effective properties of composites coinciding with its hypothesis.

Actuating and memorizing bilayer hydrogels for a self-deformed shape memory function.

A general strategy for fabricating a double layer self-deformed shape memory hydrogel which includes a thermo-responsive actuating layer and a pH-responsive memorizing layer is presented. Compared with traditional shape memory polymer systems, the temporary shape of the hydrogel could be generated by a thermo-responsive actuating layer upon the trigger of heat without the need for an external force, which could be further memorized by the pH-responsive memorizing layer.