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Alloying elements segregating to grain boundaries (GBs) is vital in determining structural stability and mechanical properties of alloys, especially in high‐entropy alloys (HEAs) that consist of multiple elements. However, some details remain unclear, such as the process of varied atoms (Cr and Co) cosegregation to GBs in FeNiCrCo alloy. Therefore, the competition and cooperation between Fe, Ni, Cr, and Co atoms segregating to GBs of FeNiCrCo alloy were investigated via molecular dynamic (MD) simulation. Five [110] symmetric tilt GBs of FeNiCrCo were applied to study the relation between the tendency of atomic segregation especially Cr and Co and GB characters including GB energy and GB excess free volume (GB excess volume). A competitive segregation phenomenon between Cr and Co atoms was discovered, which could be dominated by GB excess volume and different atomic radii among components. [ABSTRACT FROM AUTHOR]

Exploiting dual‐functional photoelectrodes to harvest and store solar energy is a challenging but efficient way for achieving renewable energy utilization. Herein, multi‐heterostructures consisting of N‐doped carbon coated MoS2 nanosheets supported by tubular TiO2 with photoelectric conversion and electronic transfer interfaces are designed. When a photo sodium ion battery (photo‐SIB) is assembled based on the heterostructures, its capacity increases to 399.3 mAh g−1 with a high photo‐conversion efficiency of 0.71 % switching from dark to visible light at 2.0 A g−1. Remarkably, the photo‐SIB can be recharged by light only, with a striking capacity of 231.4 mAh g−1. Experimental and theoretical results suggest that the proposed multi‐heterostructures can enhance charge transfer kinetics, maintain structural stability, and facilitate the separation of photo‐excited carriers. This work presents a new strategy to design dual‐functional photoelectrodes for efficient use of solar energy. [ABSTRACT FROM AUTHOR]

The high electrochemical performance of Li2MnO3‐derived Li‐rich layered oxides suggests that Na2MnO3 might be a promising cathode material for sodium‐ion batteries for its effective anionic oxygen redox. However, experimental and theoretical evidence for anionic redox and enhanced Na+ capacity of Na2MnO3 has not been established. In the present work, the structural and thermal stability, and the anionic oxygen redox mechanism of Na2MnO3 were studied by using first‐principle calculations based on density functional theory. About 1.75 Na+ per formula unit were extracted from Na2‐xMnO3 through partial O2− oxidation while the local structure remained intact, resulting in a large theoretical capacity of 315 mA h g−1. Surface Na+ was extracted before bulk Na+, which might have led to oxygen loss and structural transformation from the surface to the material bulk. Given the importance of high capacity in practical applications, Na2MnO3 and its derived Na‐rich layered oxides might be considered promising cathode materials for sodium ion batteries. [ABSTRACT FROM AUTHOR]

The popularity of portable and wearable flexible electronic devices, coupled with the rapid advancements in military field, requires electromagnetic interference (EMI) shielding materials with lightweight, thin, and flexible characteristics, which are incomparable for traditional EMI shielding materials. The film materials can fulfill the above requirements, making them among the most promising EMI shielding materials for next‐generation electronic devices. Meticulously controlling structure of composite film materials while optimizing the electromagnetic parameters of the constructed components can effectively dissipate and transform electromagnetic wave energy. Herein, the review systematically outlines high‐performance EMI shielding composite films through structural design strategies, including homogeneous structure, layered structure, and porous structure. The attenuation mechanism of EMI shielding materials and the evaluation (Schelkunoff theory and calculation theory) of EMI shielding performance are introduced in detail. Moreover, the effect of structure attributes and electromagnetic properties of composite films on the EMI shielding performance is analyzed, while summarizing design criteria and elucidating the relevant EMI shielding mechanism. Finally, the future challenges and potential application prospects of EMI shielding composite films are prospected. This review provides crucial guidance for the construction of advanced EMI shielding films tailored for highly customized and personalized electronic devices in the future. [ABSTRACT FROM AUTHOR]