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Calcium sulfate whiskers (CSW) exhibit significant surface polarity and high surface energy, leading to aggregation when directly incorporated into polymer matrices, significantly affecting the mechanical properties of the composites. Sodium oleate (SO) was used to modify CSW, introducing –C=C– active groups on the surface, followed by in‐situ graft polymerization of sodium oleate‐modified CSW (SO‐CSW) with methyl methacrylate (MMA) to prepare CSW‐g‐PMMA composites. The modification mechanism of SO and PMMA on CSW, as well as the surface modification effects on CSW, were studied using DRIFT, XRD, XPS and TEM. The results show that oleic acid ions adsorb onto the surface of CSW in two forms. One is chemisorption, in which the oleic acid ions are adsorbed on the calcium ions site on the surface of CSW in a bridging way. The other is physical adsorption, oleic acid ions and dissolved calcium ions in the form of precipitation adsorbed on the outermost layer of CSW. After in‐situ polymerization, PMMA was successfully grafted onto the surface of CSW, and the thickness of the surface PMMA coating layer was approximately 67 nm. CSW‐g‐PMMA was used as a filler in the melt blending with polypropylene (PP) to prepare PP composites. CSW‐g‐PMMA mainly toughens and enhances the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. Highlights: The mechanism of sodium oleate modified calcium sulfate whisker (CSW) has been investigated. One is chemical adsorption that the oleic acid ions are adsorbed on the calcium ions site on the CSW surface in a bridge way. The other is physical adsorption that oleic acid ions and dissolved calcium ions are adsorbed in the form of precipitation on the outer layer of CSW.After the modification of sodium oleate, the active group –C=C– was introduced on the surface of CSW, and then the PMMA long chain polymer was grafted with an in‐situ polymerization to form a PMMA coating layer with a thickness of about 67 nm, which significantly improved the hydrophobicity of CSW surface.After modification with sodium oleate and PMMA grafting, the modified CSW significantly toughened and enhanced the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. [ABSTRACT FROM AUTHOR]

To improve the sinterability, a new LATP-x wt% LiBiO3 composite solid electrolyte was fabricated by adding LiBiO3 to a NASICON-type Li1.5Al0.5Ti1.5(PO4)3 (LATP) solid electrolyte synthesized by the sol–gel method. The results showed that the liquid phase formed by the LiBiO3 additive promoted grain growth during the sintering process, which led to structural stability and an increased relative density of LATP. When the LiBiO3 addition amount was 2 wt%, the relative density was 94%, and the bulk ionic conductivity was 2.91 × 10−4 S cm−1. In addition, to improve the interfacial instability between the solid electrolyte and lithium metal, we prepared a PPS/LATP-LiBiO3/PPS composite solid electrolyte with a sandwich structure using a polymer PVDF-HFP-PEO-SN (PPS) cladding method to construct an LFP/SSCEs/Li all-solid-state battery. The electrical property test results showed that the all-solid-state battery still had 92% discharging capacity and nearly 100% coulombic efficiency after 50 cycles at 25 °C and 0.1 C. [ABSTRACT FROM AUTHOR]

In order to improve the conversion and transmission efficiency of the photoelectron, core–shell spheroid structure titanium dioxide/cadmium sulfide (TiO2/CdS) composites were synthesized as epoxy-based coating fillers using a simple hydrothermal method. The electrochemical performance of photocathodic protection for the epoxy-based composite coating was analyzed by coating it on the Q235 carbon steel surface. The results show that the epoxy-based composite coating possesses a significant photoelectrochemical property with a photocurrent density of 0.0421 A/cm2 and corrosion potential of −0.724 V. Importantly, the modified composite coating can extend absorption in the visible region and effectively separate photoelectron hole pairs to improve the photoelectrochemical performance synergistically, because CdS can be regarded as a sensitizer to be introduced into TiO2 to form a heterojunction system. The mechanism of photocathodic protection is attributed to the potential energy difference between Fermi energy and excitation level, which leads to the system obtaining higher electric field strength at the heterostructure interface, thus driving electrons directly into the surface of Q235 carbon steel (Q235 CS). Moreover, the photocathodic protection mechanism of the epoxy-based composite coating for Q235 CS is investigated in this paper. [ABSTRACT FROM AUTHOR]

The synergistic effect of chloride ions and industrial corrosive gases in the atmosphere intensifies metal corrosion. Therefore, the study of this corrosive behavior and its effects on metals in complex environments is crucial. In this study, the wet/dry cyclic corrosion test, under a constant deposited salt, was used to simulate atmospheric corrosion conditions. In addition, the methods of corrosion weight gain, dynamic potential polarization curves, electrochemical impedance spectroscopy, and other analyses were used to explore the mechanism and law of Q235 steel with different corrosion times in different coastal‐industrial atmospheric environments. The corrosion pattern of Q235 steel and the composition of the rust layer were further investigated through X‐Ray Diffractometer analysis and Scanning Electron Microscope observations. The results show that the content of Fe3O4 decreases at higher chloride ion concentrations and the content of α‐FeOOH increases in later stages of corrosion. [ABSTRACT FROM AUTHOR]

Spherical porous hollow Fe3(PO4)2/C composites with graftonite crystals were prepared in a mixed solvent of water and ethylene glycol by the solvothermal method. Then, olivine-structured LiFePO4/C was successfully synthesized by a solid phase reaction using Fe3(PO4)2/C as the precursor mixed with nanospherical Li3PO4. The experimental results show that different proportions of mixed solvents have important effects on the morphology and carbon content of Fe3(PO4)2/C, which further influence the electrochemical properties of LiFePO4/C. Compared with LiFePO4/C prepared with FePO4 as the precursor, LiFePO4/C prepared using Fe3(PO4)2/C with a water/ethylene glycol ratio of 1:1 as the precursor shows a better electrochemical performance with a discharge capacity of 165 mAh/g and a capacity retention rate of 96% over 100 cycles at 0.5 C. Using porous hollow Fe3(PO4)2/C as the precursor for preparing LiFePO4/C is beneficial to the lithium-ion escaping and embedding during the process of charging and discharging, enhancing the discharge capacity and cycle stability of the cathode material. [ABSTRACT FROM AUTHOR]

In this work, a ternary TiO2/Graphene oxide/Polyaniline (TiO2/GO/PANI) nanocomposite was synthesized by in situ oxidation and use as a filler on epoxy resin (TiO2/GO/PANI/EP), a bifunctional in situ protective coating has been developed and reinforced the Q235 carbon steel protection against corrosion. The structure and optical properties of the obtained composites are characterized by XRD, FTIR, and UV–vis. Compared to bare TiO2 and bare Q235, the TiO2/GO/PANI/EP coating exhibited prominent photoelectrochemical properties, such as the photocurrent density increased 0.06 A/cm2 and the corrosion potential shifted from −651 mV to −851 mV, respectively. The results show that the TiO2/GO/PANI nanocomposite has an extended light absorption range and the effective separation of electron-hole pairs improves the photoelectrochemical performance, and also provides cathodic protection to Q235 steel under dark conditions. The TiO2/GO/PANI/EP coating can isolate the Q235 steel from the external corrosive environment, and may generally be regarded a useful protective barrier coating to metallic materials. When the TiO2/GO/PANI composite is dispersed in the EP, the compactness of the coating is improved and the protective barrier effect is enhanced. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) semiconductors with excellent electronic and optical properties provide a great prospect for the fundamental research and application for the next-generation devices. Exploring the contact properties between 2D semiconductors and metal electrodes for improving the performance of nanodevices is of utmost importance. Motivated by the successful synthesis of bulk ScSI experimentally in a recent work [A. M. Ferrenti, M. A. Siegler, S. Gao, N. Ng and T. M. McQueen, Chem. Mater. , 2022, 34 , 12, 5443-5451], here we systematically investigate the intrinsic structural, electronic and optical properties of the novel monolayer ScSX (X = I, Br, and Cl) and their interfacial contact properties with the metal electrode of borophene using first-principles calculations. Interestingly, halogen X atoms with different electronegativities not only influence the intrinsic properties of monolayer ScSX, but also affect the interlayer coupling between monolayer ScSX and metallic borophene. The ScSI/borophene heterostructure forms a p-type Schottky contact, while both ScSBr/borophene and ScSCl/borophene heterostructures form a n-type Schottky contact. Moreover, our calculations demonstrate that strain engineering and applying an external electric field are effective strategies to regulate the Schottky barrier and contact types at the interface of ScSX/borophene. These findings provide a very promising path for designing tunable Schottky nanodevices with high-performance based on monolayer ScSX.