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Lithium-ion batteries (LIBs) have become commercialized technologies for the modern and future world, but commercial batteries using graphite still have a low specific capacity and are concerned with safety issues. Silicon (Si) and antimony (Sb) nanocomposites have the tendency to be synthesized as high-energy-density anode materials which can be a solution for the above-mentioned problems. This work reported the synthesis methods and characterization of Sb and Si composited with nitrogen-doped graphene (SbSi/NrGO) by facile chemical method and thermal treatment. Si was obtained by magnesiothermic reduction of SiO₂ derived from rice husk, waste from the agricultural process. To study the phases, particle distributions, and morphologies, all prepared composites were characterized. In this experiment, the phase compositions were confirmed as $c$-Si, $t$-Si, SiC, Sb, and shifted peaks of expanded C which were caused by NrGO synthesis. Interestingly, a good distribution of Si and Sb particles on the NrGO surface was obtained in 15Sb15Si/NrGO composition. It could be due to appropriate Sb and Si contents on the NrGO surface area in composite materials. Morphological identification of synthesized products represented the Sb and Si particles in nanoscale dispersed on thin wrinkled-paper NrGO. These results suggested that the synthesis method in this paper is appropriate to prepare SbSi/NrGO nanocomposites to be used as high-performance anode materials in high-performance LIBs for advanced applications.

In this report, the porous Fe₃O₄/C nanocomposites were successfully synthesized by using ferrocene as raw material and dilute nitric acid as solvent via extremely convenient and low-cost one-step calcining method. The formation of porous structure resulted from the aggregation and assembly of numerous nanoparticles. The experimental results show that the crystallinities, morphologies and electrochemical performance of samples were affected by the calcining temperature and carbon content. As an anode for lithium-ion batteries (LIBs), the Fe₃O₄/C nanocomposites obtained at calcination temperature of 500^∘C (Fe₃O₄/C-a500) exhibited remarkable initial specific discharge capacity of 1418mAh g${}^{-1}$ and a reversible capacity retention of 721mAhg${}^{-1}$ after 100 cycles at the current density of 100mAg${}^{-1}$. The excellent properties can be attributed to the high theoretical capacity of Fe₃O₄, the high conductivity of carbon and especially the porous structure, which offered more sites for the storage and insertion of Li ions. Even at the current density of 1000mAhg${}^{-1}$, the reversible capacity of Fe₃O₄/C-a500 can be up to 291mAhg${}^{-1}$, indicating the prepared typical nanocomposite presented excellent electrochemical performances and lithium storage capacity, which may be a promising candidate as the anode material for LIBs.

In this study, SnO₂ nanorods are successfully prepared by simple template-free hydrothermal method without surfactant. SnO intermediate with lamellar morphology is first formatted by hydrothermal method and SnO₂ nanorods are obtained after calcinations. The results of XRD characterization show that lamellar structured SnO intermediate has preferred orientation in 0 0 1 direction. According to supposed mechanism during formation process of SnO2 nanorods, tiny crystal nucleus of Sn(OH)₂ and a bit of SnCO₃ are generated from SnCl₂ and urea. Then the crystal nucleus gather together to form a nanorod. With continued reaction, nanorods gather together to form sheets and the sheets grow up to lamellar morphology and the intermediate decomposes into SnO because of the hydrothermal process. The SnO intermediate convert to SnO₂ with sheets breaking to nanorods after calcination. The results of galvanostatic cell cycling show that SnO₂ particle has high specific discharge capacity capacity. This experiment of SnO₂ nanorod preparation provides us an effective way of easy processing, low cost, and more environmentally synthesis strategy to synthesize SnO₂ nanorods.

A novel approach to fabricate sandwich-like graphene-supported mesoporous SnO₂ nanosheets (G-SnO₂) as anode materials for lithium-ion batteries (LIBs) was developed. The obtained sandwich-like G-SnO₂ inherit the typical two-dimensional structure of graphene and possess a high specific surface area (64m²g${}^{-1}$), nanosized SnO₂ particles (about 3nm in diameter), mesoporous structure (a pore size of mainly $\sim$3.8nm), large aspect ratio and enhanced electrical conductivity. As a consequence, the G-SnO₂ anode significantly improved the LIBs capacity and cycle performance (536mAhg${}^{-1}$ at 500mAg${}^{-1}$ even after 500 cycles).

LiV₃O₈ nanorod material was prepared by a simple sol–gel method. The electrochemical properties of the as-prepared LiV₃O₈ in 0.5 M Li₂SO₄ aqueous electrolyte were studied through cyclic voltammograms (CV) and discharge–charge measurements. Experiments show that this nanorod material can deliver the capacities of 72, 62 and 53 mAh/g at 20, 50, 100 mA/g, respectively. After 50 cycles, it can maintain 64, 47 and 40 mAh/g, corresponding to 88%, 76% and 77% of the initial capacities, which suggest that this nanorode material presents good cycling performance as anode material for aqueous rechargeable lithium batteries.

In this work, we evaluate the physicochemical properties of Sr${}_{2-x}$Ba_xMMoO₆ (M $=$ Mg, Mn, Fe) double perovskites as alternative anode materials for solid oxide fuel cells, for which the effect of substitution of strontium by barium in a full range of compositions is studied. The crystal structure, microstructure, characterization of transport properties (electrical conductivity, Seebeck coefficient) and oxygen content as a function of temperature, as well as chemical stability in oxidizing and reducing conditions are discussed. Fe- and Mo-containing Sr${}_{2-x}$Ba_xFeMoO₆ oxides show very high total conductivities with values of 100–1000 S$\cdot$cm${}^{-1}$, while Sr${}_{2-x}$Ba_xMgMoO₆ present good redox stability.

Metal phosphide has recently been considered as a promising advanced anode material for sodium storage. This review focuses on recent development of metal phosphides anode designs for sodium ion battery (SIB). Based on these advanced design strategies, a comprehensive summary of the structural features and storage mechanisms of the metal phosphide-based electrode are developed. Moreover, the future challenges and perspective faced by metal phosphides anodes for SIB are also delineated.

A flexible strategy is to exploit encapsulating Si nanoparticles into N-doping carbon film (Si-NC) that can effectively localize the Si nanoparticles, thereby solving the problem of serious volume change during cycling as well as facilitating the fast diffusion of Li${}^{+}$, and thus achieving improved anode performance. A maximum capacity of 883.1mAhg${}^{-1}$ at the current density of 100mAg${}^{-1}$ after 50 charge and discharge processes is achieved for Si-NC. Even at a large current density of 2000mAg${}^{-1}$, a specific capacity of 415mAhg${}^{-1}$ is maintained. Moreover, the charge capacity can still almost recover the initial capacity as the current density is reverted to 100mAg${}^{-1}$, indicating that Si-NC has a superior rate performance in lithium storage. This facile synthesis route provides a new perspective to produce Si/C composite at a low cost and large scale with good electrochemical performance.

As anode material for lithium-ion batteries, graphite has the disadvantage of relatively low specific capacity. In this work, a simple yet effective strategy to overcome the disadvantages by using a composite of flake graphite (FG) and small-sized graphene (SG) has been developed. The FG/SG composite prepared by dispersing FG and SG (90:10 w/w) in ethanol and drying delivers much higher specific capacity than that of individual component except for improved rate capability. More surprisingly, FG/SG composite delivers higher reversible capacity than its theoretical value calculated according to the theoretical capacities of graphite and graphene. Therefore, a synergistic effect between FG and SG in lithium storage is clearly discovered. To explain it, we propose a model that abundant nanoscopic cavities were formed due to physical adhesion between FG and SG and could accommodate extra lithium.

We report a facile chemical vapor deposition (CVD) method to grow silicon/carbon (Si/C) microspheres on commercial graphite microsphere (GMs) surface to prepare Si/C/GMs composite anode materials for Li-ion batteries. The CVD synthesis is conducted at 900°C using methyltrichlorosilane (CH₃SiCl₃) as both the Si and C precursor, which is a cheap byproduct in organosilane industry. The samples are characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, Raman spectroscopy and X-ray photoelectron spectroscopy. It is found that the obtained Si/C/GMs composites are composed of Si nanocrystals, amorphous carbon and GMs. The CVD time significantly influences the morphology and electrochemical performance of the Si/C/GMs composite materials. The Si/C/GMs composite materials prepared at CVD condition of 900°C for 4 h possess improved electrochemical properties, showing a discharge capacity of 821.4 mAh g⁻¹ at a rate of 50 mA g⁻¹, and a good cycling performance (i.e., a reversible capacity of 565.2 mAh g⁻¹ is retained after 50 cycles). The enhanced electrochemical performance is attributed to the formation of Si/C microsphere network among GMs, which increases the electronic conductivity and is able to buffer the large volume changes of Si during lithium ion insertion/extraction.

More and more scholars were committed to loading the iron oxide nanoparticles on the graphene. Shown in the studies, there were many nucleation sites on the graphene for the Fe₃O₄ particles, meanwhile, the distance between the graphene was lengthened due to the magnetic Fe₃O₄ particles, and the reunion of the graphene could be avoided. The excellent performance of the two materials was combined perfectly in this way. To facilitate the researchers work better in the future, in this paper, the synthesis of Fe₃O₄/graphene were reviewed from its applications such as waste water treatment, magnetic targeting drugs, biosensor, and the anode materials for lithium-ion battery. Simultaneously, the prospects of the composite material were discussed.