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An unconventional spheric quasi-SEI film is strategically configured on cost-effective red phosphorus. Highly activated surface with weakened P P bond strength and strengthened binding force increase the electrode integration. [Display omitted] • A method for moderate phosphorylation and etching of phosphorus surface. • An unconventionally spheric quasi-SEI film forms before lithiating progress. • Balls change from solid core–shell structure to hollow core–shell sphere structure. • Highly activated surface with weakened P P bond strength. • Highly activated surface strengthened binding force of PVdF. Solid electrolyte interface (SEI) film is the most important separation layer between nonaqueous electrolytes and anodes to protect anode from corrosion and maintain continuous ionic diffusion tunnels. However, SEI film, especially for high-capacity anode materials, is still confined to continuous and stable ionic conductive layer despite the conventional SEI film is intrinsically poor to resist against the drastic volumetric changes of active centers. Herein, an unconventional spheric quasi-SEI film is thus strategically configured on cost-effective red phosphorus electrode materials by moderate phosphorylation combined with pore-forming process. Microstructure adjustment from solid microspheres structure to hollowed core–shell spheres is visibly taken place on this amazing spheric quasi-SEI film during the stabilization. Benefiting from the highly activated surface with weakened P P bond strength and the strengthened binding force between phosphorus and binders, the optimized phosphorus anode presents an outstanding long-term durability with a high discharge capacity of 1126.4 mAh/g over 400 cycles at 200 mA g−1 even at a high phosphorus load ratio of 70 wt%. This revolutionary configuration of quasi-SEI film provides high-capacity anode materials subject to large volumetric changes an unconventional approach from dependence on conductive framework/matrix. [ABSTRACT FROM AUTHOR]

In this work, pulse electrodeposition method was proposed to directly deposit amorphous carbon coating (ACC) onto 316L stainless steel substrate in choline chloride-ethylene glycol deep eutectic solvent (DES) mixed with ammonium chloride (NH 4 Cl) to fabricate bipolar plates. The obtained dense ACC has a thickness of ∼400 nm. Potentiodynamic and potentiostatic polarization tests demonstrated that the corrosion current density of ACC coated 316L steel was of the order of 10−7 A cm−2 in the simulated proton exchange membrane fuel cells (PEMFC) working environment, and the self-corrosion potential of the coating positively shifted by 0.4V, indicating a significant improvement on corrosion resistance of the coated steel plate due to excellent electrochemical stability of ACC. The Rockwell C indentation test showed that the as-obtained ACC was strongly bonded to the substrate and also had high in-plane strength. Further numerical simulation and comparison experiments showed that C was chemically bonded with Fe in the substrate, which was boosted by the assistance of NH 4 Cl. The intact and strong bonding between ACC and the substrate is highly helpful to improve corrosion resistance. The success in coating stainless steel plate with ACC by pulse electrodeposition method provides a promising alternation for coating of proton exchange membrane electrolyzer cell (PEMEC) and PEMFC metal bipolar plates. • Amorphous carbon coating (ACC) has prepared by electrodeposition on 316LSS. • The ACC was strongly bonded to the substrate and had high in-plane strength. • With the assistance of NH 4 Cl, C was chemically bonded with Fe in the substrate. [ABSTRACT FROM AUTHOR]

[Display omitted] • Environmentally-friendly one-step novel method for producing rGO films. • Scale production of high-quality rGO thin films. • Applications in flexible transparent conductive films and supercapacitor electrodes. • Investigation of GO reduction mechanism, achieving valuable insights. The reduced graphene oxide (rGO) thin films have attracted much attention in flexible electronic devices and supercapacitors (SCs). However, the chemical reduction mechanism of GO needs to be clarified, and the one-step process at low temperatures for preparing high-quality rGO thin films from GO dispersions is still blank in the research field. Here, we propose a one-step operation to spray GO dispersions onto substrate or current collector under a hydroiodic acid (HI) atmosphere while simultaneously achieving the preparation of rGO thin films. This pioneering metal-free, transfer-free, fast, low-temperature, environmentally friendly, and scalable spraying technology enables large-scale production of high-quality rGO. This method realizes the preparation of highly conductive and high transmittance rGO thin films on flexible polyimide and polyethylene terephthalate substrates, as well as the preparation of rGO thin films on current collectors as SCs electrodes. Density functional theory calculations show that oxygen-containing functional groups on the surface of GO exhibit a stronger adsorption energy for HI, and have a low energy barrier during reduction by HI. Ab initio molecular dynamics simulated the possible reduction reaction path between GO and HI at 90 °C, demonstrating that HI molecules can effectively reduce GO. Furthermore, the sheet resistance of the transparent conductive film created using the method developed in this study reaches approximately 1000 Ω/sq (80 % transparency), and the specific capacitance of the SCs electrode film created in this method is 433.2 F/g (5 mV/s, 1 M H 2 SO 4). Our study not only validates the efficacy of the one-step synthesis method for rGO thin films but also provides theoretical insights into the underlying reaction mechanism. This work holds significant promise for advancing applications in various electronics by facilitating large-scale production of high-quality rGO thin films. [ABSTRACT FROM AUTHOR]

The traditional MoSe 2 anode material for lithium-ion batteries has poor cyclic stability and relatively low capacity, which hinders its practical application. Herein, high capacity of Si and Se are exploratively incorporated into two-dimensional MoSe 2 nanopetals to configure Se@MoSe 2 /Si composite. The optimized Se@MoSe 2 /Si composites have both high capacity and good electrochemical stability with a high retention capacity of 1187.7 mAh/g after 200 cycles at 100 mA/g current density. The visible depression on volumetric expansion is observed on the configuration of Se@MoSe 2 /Si. The admirable function of silicon on the enhancement of the electrochemical activity and the conductivity of Se@MoSe 2 is theoretically demonstrated by First-principles calculations. This mutually beneficial interaction between the components demonstrates a promising synergistic effect on Se@MoSe 2 /Si. [ABSTRACT FROM AUTHOR]

Red phosphorus for lithium-ion batteries (LIBs) is considered to be promising electrode material due to the high theoretical capacity and moderate working potential. However, the enormous volumetric expansion and intrinsic poor electrical conductivity result in poor interfacial stability and sluggish reaction kinetics. Herein, different functional conductive polymers are introduced to modify the interface, aiming to improve the interfacial compatibility and mechanical stability between red phosphorus and matrix materials. The Cobalt polyphthalocyanine (CoPPc)/polydopamine (PD) hybrid interface not only facilitates electron transfer within the system, but also accommodate the volume expansion of red phosphorus. Consequently, the novel P/CoPPc@PD anode achieves a stable specific capacity of 650 mAh g−1 after 580 cycles at 200 mA g−1, and a discharge capacity of 385 mAh g−1 at 5.0 A g−1 even after 10,000 cycles, demonstrating outstanding long-term cycling stability and rate performance. The synergistic interfacial effects of CoPPc and PD not only improve the conductivity of the anode material, but also constructs a mechanical buffering layer for the volume expansion of phosphorus. Hence, the rational design strategy of P/CoPPc@PD anode for LIBs reveals excellent cycle stability and promising application. [Display omitted] • Inorganic/organic hybrid interface was configured for red phosphorus. • CoPPc can facilitate the electron transport of red phosphorus anode. • The PD elastic buffer layer can alleviate the volume change of red phosphorus. • The CoPPc@PD hybrid layer improves the kinetics and structural integrity. [ABSTRACT FROM AUTHOR]

• The built-in electric field between the Mn 3 O 4 -MnS enhances the carrier transport. • The core–shell structure enables high mechanical stability. • Mediated pseudo-capacitance is induced by the configuration of Si@Mn 3 O 4 -MnS/C. • The vacancy-enriched Si@Mn 3 O 4 -MnS/C presents excellent cyclability. A configuring vacancy-enriched Mn oxide/sulfide embedded in amorphous carbon layer with highly concentrated vacancies to encapsulate silicon was tentatively explored to overcome the long-term stabilization issues of silicon active center. Our experimental results demonstrate that the configuration of vacancy-enriched Mn 3 O 4 -MnS/carbon hybrid coating layer not only functions as a physical separation layer to prevent silicon from direct contact with electrolytes, but also works as an interesting intermediator to facilitate the structure stabilization and the deep utilization of silicon core center. The surface pseudo-capacitive effect dramatically benefits to the modification of the rate performance of silicon. The synthesized Si@Mn 3 O 4 -MnS/C anode material maintains a high reversible capacity of 830 mAh/g after undergoing 200 charge–discharge cycles at 200 mA g−1 current density. [ABSTRACT FROM AUTHOR]