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The forming of Li-Bi alloy can build a lithiophilic protective layer on the lithium anode, however, it is found that the lithium dendrites trend to grow on the surface of bismuth-rich solid electrolyte interphase (SEI) and there is an exfoliation of SEI from substrate caused by de-alloying process at a large current density. The failure cause of the bismuth-rich SEI is considered as the inadequate Li-ionic conductivity of the passivation layer, which cannot facilitate the lithium deposition on the substrate. Then the components with high Li-ionic conductivities such as Li 3 N, LiF and Li 2 S are introduced into the SEI to adjust the characteristic of the bismuth-rich layer by the addition of LiNO 3 , Bi 2 S 3 and FEC. All of them enhance the SEI's performances effectively and LiNO 3 presents the best. With the addition of LiNO 3 , the SEI thickness is decreased and Li-ionic conductivity is enhanced while Li 3 N became one of the major components of the layer. Utilizing the improved bismuth-rich protective layer the Li/Li symmetric cell presents an overpotential at ∼10 mV in a long cycle over ∼1700 h at 4 mA cm−2, and the LiFePO 4 /Li cell with the cathode loading of ∼10 mg cm−2 exhibits a capacity retention rate 72.1% in 400 cycles. This work provides a new SEI design strategy for lithium metal anode operating at high current density and an inspiration for improving other functional interfacial layers in lithium batteries. • Lithium bismuth alloy and dendrites trend to dealloy and grow on the SEI at high current density. • Additives enhancing Li-ionic conductivities are introduced to adjust the bismuth-rich layer's components. • Lithium nitrate addition make Li 3 N a major component of the layer and significantly enhances SEI electrochemical properties. [ABSTRACT FROM AUTHOR]

Magnetic metal modified carbon-based composites synthesized through chemical methods have shown great potential in the field of electromagnetic wave (EMW) absorption. Biomass-derived carbon, as an alternative to traditional carbon sources, has better economic and environmental benefits. In this work，we embedded magnetic iron ions in dried agaric through multi-effect adsorption and obtained ripple-like Fe/C composites after high-temperature annealing. The effective absorption bandwidth (EAB) of Fe/C composites can reach 6.3 GHz (11.5–17.8 GHz) at 2.5 mm, achieving broadband electromagnetic response. The excellent performance can be attributed to the ripple-like carbon, which enhances the transmission path of EMW in the absorber. On the other hand, the uniform loading of Fe nanoparticles on biomass-derived carbon promotes the interface polarization and dipole polarization and coordinates the impedance matching of the composites. This study provides a reference for the design and construction of efficient biomass-derived magnetic carbon-based absorbers. [Display omitted] • Fe/C composites have been synthesized using biomass-derived method. • Fe/C composites exhibit an effective bandwidth (R L min ≤ −10 dB) of 6.3 GHz with the thickness of 2.5 mm. • The great absorption performance of Fe/C composites stems from proper impedance match and boosted dielectric-magnetic loss. [ABSTRACT FROM AUTHOR]