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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]

[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]

A novel carbon-excluded strategy to achieve performance improvement of red phosphorus is constructively explored on a simple P/S composite via cyclically constructing a dynamic hetero-interface with built-in electric fields. [Display omitted] • Despite composed of only two electron insulating components, P/S composite has excellent performance. • Periodically formed transient interface is crucial for performance improvement. • Lithiated sulfur is crucial for the formation of transient hetero-interface. • The built-in electric field provides fast diffusion tunnels for ions and electrons. Red phosphorus has attracted tremendous attention because of its high theoretical specific capacity, cost effective as well as environmental friendly characteristics. Nevertheless, its large volumetric expansion during the charge–discharge process and intrinsic poor conductivity have severely hindered the practical application of red phosphorus. A novel strategy of carbon-excluded in active materials to achieve performance improvement of red phosphorus is constructively explored by delicate interface regulations of building a dynamic hetero-interface on cycling. A very simple red phosphorus/sulfur (P/S) was prepared by moderately ball-milling process to achieve the purpose despite only two electron-insulating components of sulfur (S) and red phosphorus (P) are involved. The experiment results demonstrate that the in-situ formation of the temporary solid sheath of lithiated sulfur, which is partially incorporated in solid electrolyte interface (SEI) film around red phosphorus. It is the crucial factor to depress the decomposition of the electrolyte. Furthermore, theoretic calculations based on first-principles reveal that the built-in electric field in the transient interface of Li 2 S/P provides fast diffusion tunnels for ions and electrons, which facilitates to improve the kinetics of the electrode. Our research demonstrates the construction of dynamic hetero-interfaces have huge potentials to improve the sluggish kinetics of high capacity electrode materials. [ABSTRACT FROM AUTHOR]