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Rational designed cost-effective material is significant in the field of electric energy storage and microwave absorber. In this work, carbon coated Fe 3 C nanoparticles (NPs) encapsulated carbon nanotubes (Fe 3 C@C@CNTs) is delicately constructed through in-situ chemical vapor deposition (CVD) strategy. As a promising anode material for lithium-ion batteries (LIBs), the Fe 3 C@C@CNTs nanocomposite facilitates electron transport with intensive interfacial interaction, making it an ideal prototype to thoroughly understand the mechanisms of interatomic charge transfer mechanism. As a result, this well-designed Fe 3 C@C@CNTs anode exhibits a high reversible capacity of 1027 mAh g−1 after 150 cycles at 0.1 A g−1 and excellent cycling stability with 71 % capacity retention at 519 mAh g−1 after 1000 cycles at 1.0 A g−1. Electrochemical kinetic results confirm that the pseudocapacitance contributions reach up to 90.1 % at 1.0 mV s−1, and the higher pseudocapacitance characteristic is ascribed to the multi-dimensional encapsulated by CNT layer and carbon layer. Meanwhile, depending on the peculiar cavity structure and heterogeneous interfaces effects constructed by multi-dimensional encapsulated structure, the minimum reflection loss (RL min) of Fe 3 C@C@CNTs nanocomposite can reach up to −67.63 dB in effective absorption bandwidth (EAB) of 7.12 GHz with the optimal matching thickness of 2.28 mm, suggesting its extensive potential application as practical alternative absorber. This domain-limited growth strategy opens a new horizon to achieve multi-functional application and beyond for Fe-based nanomaterial. [Display omitted] • Fe 3 C@C@CNTs is prepared by in-situ chemical vapor deposition method. • The multi-dimensional encapsulated structure can maintain electrochemical activity and increase electronic transmission path. • The heterogeneous interfaces can provide abundant active sites for lithium-ion storage and induce significant interfacial polarization for electromagnetic wave attenuation. [ABSTRACT FROM AUTHOR]

Ruthenium phosphides are promising candidates to substitute platinum (Pt) for electrocatalytic hydrogen evolution reaction (HER) but further boosting their activity is a tremendous challenge. Herein, crystalline/amorphous Ru@RuP core-shell nanoparticle supported on carbon nanotube (Ru@RuP-CNT) was synthesized by controllable surface phosphatization procedure. The resulted Ru@RuP-CNT outperforms its Ru-based rivals and Pt/C catalyst in HER, exhibiting a tiny overpotential of 28 mV at 10 mA cm−2 and marvelous mass activity of 3.24 A mg−1 at 50 mV overpotential in alkaline solution. Further investigations show that electronic interaction between metallic Ru core and amorphous RuP shell tunes the absorption strength of hydrogen to boost the HER activity. This work exemplifies an effective strategy to enhance the electrocatalytic performance via interfacial electronic interaction and may shed light on crystalline/amorphous heterostructured catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Metal free conversion of aryl C:glyph name="sbnd" />C bond through a photochemical rearrangement/oxidation cascade reaction is described. Irradiation of O-acetyl aryloxy benzene derivatives in benzene solution undergoes a unique photochemical rearrangement reaction to afford the ketal compounds, which are sequentially oxidized by 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) to yield the diketone compounds. [Copyright &y& Elsevier]

The inert structure and high molding temperature of thermoplastic resin bring new challenges to carbon fiber (CF) sizing agents. Herein, an easily purified semi-aliphatic polyimide (SA-PI) was synthesized as CF sizing agent. The SA-PI has no significant decomposition before 300 °C and a 5% decomposition temperature of 442 °C. Based on the solubility of its polyamic acid ammonium salt, the SA-PI is configured as an aqueous solution for CF sizing. The results show the surface of sized carbon fiber (SCF) is covered with a sizing coating. At the same time, the polar group of the sizing coating increases the surface energy by 28.45%. Compared with bare CF, the tensile strength of SCF is increased by 11.43%, the ILSS and flexural strength of SCF/PEEK increased from 55.71 MPa and 485.34 MPa to68.98 MPa and 523.33 MPa, respectively. In addition, the micro-morphology at the fracture of the composite clearly proves that the sizing agent improves the interface performance of the composites effectively. Image 1 [ABSTRACT FROM AUTHOR]

The decomposition of copper(I)–NHC and silver-NHC complexes in solution under air was studied. The Cu(I)–NHCs were oxidized into urea derivatives and hydrolysed into imidazoliums or benzimidazoliums. The decomposition of Ag–NHC with a saturated backbone led to ring-opening product, while the Ag–NHC with an unsaturated backbone led to imidazolium and Ag-bisNHC complex. The effects of steric property, hydrophilicity, and binding energy of NHC to O 2 and H 2 O on the decomposition of Cu(I)–NHC were studied using theoretical calculations. Steric hindrance played an important role on the stability of Cu(I)–NHC. Pathways for the decomposition of Cu(I)–NHC and Ag–NHC were proposed. To create your abstract, type over the instructions in the template box below. Fonts or abstract dimensions should not be changed or altered. Image 1 • Decomposition of Cu(I)–NHC and Ag–NHC under air was studied.. • Decomposition of Cu(I)–NHC led to urea and hydrolysis products.. • Theoretical calculations were used to study the decomposition of Cu(I)–NHC.. • Decomposition of Ag–NHC led to ring-opening product or regenerated NHC precursor.. • This article provides a method to study the decomposition of metal-NHC under air.. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeCoNiCrMo HEA plate was prepared for efficient OER in alkaline media. • High-valence Mo/Cr cause dynamic structural/compositional evolution during OER. • Mo is rapidly oxidized and dissolved, provoking the concomitant Cr leakage. • Absorbed/intercalated MoO 4 2- facilitates the generation of active β-NiOOH. • Cr dopants in active layer enhance OER by preventing the Ni/Co over-oxidation. We herein report free-standing FeCoNiCrMo high-entropy alloy (HEA) plate as an excellent oxygen evolution reaction (OER) catalyst with activity and durability superior to benchmarking NiFe layered double hydroxide (LDH). It requires overpotentials of 303 and 372 mV to reach current densities of 100 and 700 mA cm−2, respectively, and maintains its activity for at least 120 h in alkaline media. Its dynamic structural/compositional evolution is uncovered, in which Mo metals are rapidly oxidized and dissolved into electrolyte, provoking the concomitant Cr leakage and leaving behind reconstructed active NiFeCo oxyhydroxide nanostructures on the surface. Its enhanced OER (intrinsic) activity is found to be associated with the absorption of resultant Mo oxo-anion (MoO 4 2-) and the persistence of trace Cr atoms in surficial NiFeCo oxyhydroxide phase. This work offers useful insights into the origin of high OER activity of HEA catalysts and also provides a feasible way for mass-production of active OER catalysts. [ABSTRACT FROM AUTHOR]