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To address the huge volume expansion and the severe side reactions on silicon (Si) as an anode for lithium storage, we propose a hierarchical carbon architecture to composite with Si nanoparticles. This architecture is composed of an outer carbon shell, N-doped carbon nanotubes (CNTs), and inner carbon coating, which originated from the Co-zeolitic imidazole framework (ZIF-67) and polydopamine (PDA). The cycling stability and rate capability of the Si anode for lithium storage have significantly improved because of the unique carbon architecture. Insitu transmission electron microscopy (TEM) and other physical characterization methods confirm that Si nanoparticles are highly stabilized concurrently by the outer carbon shell that buffers the volume change of Si and the inner carbon coating that prevents the Si from direct contact with the electrolyte, leading to the improved cycling stability of Si. Additionally, all of the carbon textures, i.e., N-doped CNTs, the outer carbon shell, and inner carbon coating, provide an excellent electronically conductive network, which endows the Si anode with excellent rate capability. This carbon architecture provides a promising solution to the issues present in the Si anode for its use in high energy lithium-ion batteries.

Since the inception of micro-arc oxidation technique, the research on the mechanism of micro-arc oxidation has never stopped. During this period, the research on micro-arc oxidation process of breakdown phenomenon is in depth, and the breakdown model also has been established. Because the micro-arc oxidation process involves many complicated phenomena such as heat, light, electricity, there are a lot of difficulties to deal with. Therefore it has not the perfect qualitative and quantitative model to explain all the phenomena. This paper reviewed the research progress of the mechanism of micro-arc oxidation, observed and analyzed the phenomena and the possible reactions of micro-arc oxidation process at all stages. This paper also discussed plasma’s important role in the process of micro-arc oxidation.Since the inception of micro-arc oxidation technique, the research on the mechanism of micro-arc oxidation has never stopped. During this period, the research on micro-arc oxidation process of breakdown phenomenon is in depth, and the breakdown model also has been established. Because the micro-arc oxidation process involves many complicated phenomena such as heat, light, electricity, there are a lot of difficulties to deal with. Therefore it has not the perfect qualitative and quantitative model to explain all the phenomena. This paper reviewed the research progress of the mechanism of micro-arc oxidation, observed and analyzed the phenomena and the possible reactions of micro-arc oxidation process at all stages. This paper also discussed plasma’s important role in the process of micro-arc oxidation.