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Two-dimensional (2D) “graphene-like” inorganic materials, because of the short lithium ion diffusion path and unique 2D carrier pathways, become a new research focus of the lithium storages. Some “graphene-like” binary compounds, such as, MnO2, MoS2 and VO2 ultrathin nanosheets, have been synthesized by the peeling method, which also exhibit enhanced lithium storage performances. However, it still remains a great challenge to synthesize widely-used lithium-containing ternary oxides with “graphene-like” nanostructures, because the lithium-containing ternary oxides, unlike ternary layered double hydroxides (LDH), are very hard to be directly peeled. Herein, we successfully synthesized ultrathin Li3VO4 nanoribbons with a thickness of about 3 nm by transformation from ultrathin V2O5·xH2O nanoribbons, moreover, we achieved the preparation of ultrathin Li3VO4 nanoribbon@graphene sandwich-like nanostructures (LVO/G) through the layer-by-layer assembly method. The unique sandwich-like nanostructures shows not only a high specific reversible capacitance (up to 452.5 mA h g−1 after 200 cycles) but also an excellent cycling performance (with more than 299.2 mA h g−1 of the capacity at 10C after 1000 cycles) as well as very high rate capability. Such template strategy, using “graphene-like” binary inorganic nanosheets as templates to synthesize lithium-containing ternary oxide nanosheets, may be extended to prepare other ternary oxides with “graphene-like” nanostructures.

Ti/Al/TiC mixed powders were used as the raw materials for the fabrication of functionally graded material (FGM) in situ synthesis by spark plasma sintering. The sample was analyzed by SEM combined with Metallographic microscope and Energy Disperse Spectroscopy. The results show that dense Ti2AlC/TiC functionally graded material (FGM) was produced by spark plasma sintering. Micro-hardness tester is used to character the distribution of hardness on the material .The results show that the Vickers hardness of every layer increases with TiC content and temperature increasing.

Ti/Al/TiC mixed powders were used as the raw materials for the fabrication of functionally graded material (FGM) by hot pressing sintering. The sample was analyzed by SEM combined with Metallographic microscope and Energy Disperse Spectroscopy,The results show that each layer is composed of TiC and Ti2AlC, without containing other phases. The size of TiC grains are about 3-6 μm. With TiC content in the layers increasing, Ti2AlC grains gradually decrease. The lathy Ti2AlC grains of the FGM have a length of about 10 μm and a width of about 4 μm. The interface of each layer has a good combination with a certain thickness transition layer.Microhardness tester is used to analyse the hardness of material.The results show that the Vickers hardness of every layer increases with TiC content increasing. The thermal shock performance test found that material has good thermal shock performance.