asymmetrical distribution of lithium resource. [3,4] On the other hand, sodiumion batteries (SIBs) have attracted great attention due to its abundant sodium resource, low cost, and the similar electrochemical reaction to LIBs, which is considered as the promising battery technology for large-scale energy storage applications. [5,6] But the commercial graphite does not work for SIBs as its interlayers are incapable to accommodate the sodium ions with larger ionic size. [7] As a result, one promising step to make the technological advancements is to develop the novel anode materials with both lithium and sodium storage ability.In this regard, transition metal oxides (M a O b , M = Mn, Fe, Co, Ni, Cu, etc.) based on the conversion reaction mechanism have been widely explored as the potential anode materials for LIBs and SIBs. Compared to graphite, transition metal oxides can provide higher theoretical specific capacity and higher safety, because the higher reaction potential can eliminate the lithium/sodium dendrite problem. [8][9][10][11][12][13][14][15] As an important member in the transition metal oxide family, transition metal vanadate has attracted much attention due to the multivalent properties of vanadium, which could deliver considerable capacity based on the multielectron transfer. [16,17] Additionally, the vanadium oxide presents strong VO bond during electrochemical process, suggesting the smaller volume change compared with traditional conversion-type electrodes. [18] For LIBs application, it is reported that the vanadium oxide can store lithium ions on the basis of the intercalation reaction mechanism, and provide the reaction sites for the conversion reaction between transition metal and metal oxide, preventing the aggregation of the obtained highly active metal nanograins, improving the cycling performance of the active material. [19,20] Furthermore, the binary metal oxide could exhibit higher electrochemical activity compared to the single metal oxide electrode. [21] Calcium vanadate nanowires have been synthesized as a novel sodium-ion anode material, which delivered a superior cycling performance (1600 cycles), excellent rate performance (5000 mA g −1 ), and an applicable reversible capacity (>300 mA h g −1 ). [16] Lou's group has developed triple-shelled Preventing the aggregation of nanosized electrode materials is a key point to fully utilize the advantage of the high capacity. In this work, a facile and lowcost surface solvation treatment is developed to synthesize Fe 2 VO 4 hierarchical porous microparticles, which efficiently prevents the aggregation of the Fe 2 VO 4 primary nanoparticles. The reaction between alcohol molecules and surface hydroxy groups is confirmed by density functional theory calculations and Fourier transform infrared spectroscopy. The electrochemical mechanism of Fe 2 VO 4 as lithium-ion battery anode is characterized by in situ X-ray diffraction for the first time. This electrode material is capable of delivering a high reversible discharge capacity of 799 mA h g −1 ...

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The application of transition-metal oxides in the energy storage field is hampered by its low electronic conductivity, sluggish Li + diffusion, and huge volume changes. The construction of oxygen vacancy defects can effectively modify the electronic structure of the active materials, accelerating the charge transfer process. Herein, the CoMoO 4 nanorods with different oxygen vacancy concentrations are synthesized through the facile calcination process under N 2 and Air atmospheres. The ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) analysis and Density Functional Theory (DFT) calculation results confirm that the bandgap reduces along with the increment of the oxygen vacancy content. The CoMoO 4-N 2 with higher oxygen vacancy concentration exhibits more superior electrochemical performance than CoMoO 4-Air, which delivers an ultrahigh specific capacity (999 mA h g À 1 after 500 cycles at 0.5 A g À 1), remarkable rate capacity (477 mA h g À 1 at 9 A g À 1), and excellent cycling stability (650 mA h g À 1 after 1000 cycles at 2 A g À 1).

The binary transition metal oxides have attracted great attention because of their considerable energy and power densities. However, they suffer from low reaction kinetics and large volume change, limiting their practical energy applications. The construction of a mesoporous structure with a large surface area, the development of a carbon matrix, as well as heteroatom doping can effectively overcome the above challenges. Herein, the synthesis of phosphorous‐containing Fe2VO4/nitrogen‐doped carbon mesoporous nanowires (P‐Fe2VO4/NCMNWs) is reported. In this unique structure, the atomic‐level P‐doping could increase the conductivity of Fe2VO4 by reducing its band gap, which is confirmed by DFT calculations. Furthermore, the phosphorus can covalently “bridge” the carbon layer and Fe2VO4 through P−C and Fe−O−P bondings. As a result, this anode material exhibits a high capacity (1002 mA h g−1 at 0.5 A g−1 after 250 cycles), excellent rate performance (448 mA h g−1 at 10 A g−1), and prominent long‐term cycling stability (533 mA h g−1 at 5 A g−1 after 500 cycles, 364 mA h g−1 at 10 A g−1 after 1000 cycles). All of these attractive features make the P‐Fe2VO4/NCMNWs a promising electrode material for high‐performance lithium‐ion batteries.

Gold nanomaterials have shown promising applications in catalysis and sensing. Among the current directions in the research and development of gold catalysts, the exploration of new forms is one of the major priorities. Using bacteria as the supporting template and polystyrene spheres as the pore‐generation template, a hierarchical‐template synthesis strategy was developed in the present study to synthesize hollow nanoporous gold rods. The pore size can be easily adjusted by using polystyrene spheres (PSS) with different diameters as the template (the pore size is about 160 nm and 70 nm when using 200 nm and 110 nm PSS, respectively, as the template). Moreover, with the simple sol–gel method, different amounts of TiO2 can be coated on these nanoporous gold rods. The results showed the thermal stability and catalytic activity of the nanoporous gold rods were improved dramatically with moderate TiO2 coating. Using reduction of 4‐nitrophenol to 4‐aminophenol with sodium borohydride as the model reaction, excellent catalytic properties (reaction rate constant k=0.246 min−1) of the prepared TiO2‐coated gold rods catalysts were confirmed.