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Transition-metal selenides have been recognized as a class of promising anode materials for sodium-ion batteries (SIBs) on account of their high capacity. Nevertheless, the sluggish conversion kinetics and rapid capacity decay caused by insufficient conductivity and volume change restrain their applications. Herein, hollow heterostructured bimetallic selenides embedded in an N-doped carbon nanoframework (H-CoSe 2 /ZnSe@NC) were prepared via a facile template-engaged method. Benefiting from the rich defect at the phase boundary of the CoSe 2 /ZnSe heterostructure, pre-reserved cavity, and enhanced structure rigidity, the abovementioned issues are resolved at once, and the accelerated charge transportation kinetics traced by spectroscopy techniques and theoretical calculations certify the interface effect in the capacity release. In addition, ex situ X-ray photoelectron spectroscopy, X-ray diffraction, and high-resolution transmission electron microscopy all confirm the high-reversible electrochemical conversion mechanism in H-CoSe 2 /ZnSe@NC. Together with a reasonable structural architecture and the highly reversible conversion reaction, H-CoSe 2 /ZnSe@NC displays a prominent rate capacity (244.8 mA h g −1 at 10 A g −1 ) as well as an ultralong lifespan (10,000 cycles at 10 A g −1 ), highlighting the significance of structure control in fabricating high-performance anodes for SIBs.

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High-hardness and wear-resistant ceramic coatings were obtained on 5052 aluminum alloy by the microarc oxidation (MAO) process in silicate electrolytes with different nanoadditives (TiO2, Si3N4), and the effects of different nanoadditives on the microstructural and mechanical properties of the ceramic coatings were systematically studied. The microstructure results revealed that the nanoadditives could improve the thickness and compactness of the ceramic coatings. The X-ray diffraction results demonstrated that the nanoadditives were successfully incorporated into the MAO coatings and that some new phases of Si2N2O and TiN were formed, enhancing the comprehensive performance of the ceramic coatings. Furthermore, the distributions of elements determined from energy-dispersive X-ray (EDX) spectroscopy and cross-sectional images displayed a good homogeneity to support the excellent mechanical properties of the ceramic coatings. Therefore, the average microhardness, the full indentation force–depth curves, the hardness and elastic modulus, and the H/E and H 3/E 2 ratios of the ceramic coatings with TiO2 and TiO2 + Si3N4 nanoadditives delivered a very high hardness, implying good antifriction properties. Moreover, the friction coefficients of the ceramic coatings also demonstrated their outstanding wear resistance. Finally, the corrosion resistance and electrochemical impedance spectroscopy results further revealed the compactness of the ceramic coatings, indicating a high hardness and abrasion resistance.

Analogous graphite carbon sheets from corn stalks have been synthesized via a simple high temperature carbonization and expansion process, which showed superior sodium ion storage performance.

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