MoSe 2 grown on N,P-co-doped carbon nanosheets is synthesized by a solvothermal reaction followed with a high-temperature calcination. This composite has an interlayer spacing of MoSe 2 expanded to facilitate sodiumion diffusion, MoSe 2 immobilized on carbon nanosheets to improve chargetransfer kinetics, and N and P incorporated into carbon to enhance its interaction with active species upon cycling. These features greatly improve the electrochemical performance of this composite, as compared to all the controls. It presents a specific capacity of 378 mAh g −1 after 1000 cycles at 0.5 A g −1 , corresponding to 87% of the capacity at the second cycle. Ex situ Raman spectra and high-resolution transmission electron microscopy images confirm that it is element Se, rather than MoSe 2 , formed after the charging process. The interaction of the active species with modified carbon is simulated using density functional theory to explain this excellent stability. The superior rate capability, where the capacity at 15 A g −1 equals ≈55% of that at 0.5 A g −1 , could be associated with the significant contribution of pseudocapacitance. By pairing with homemade Na 3 V 2 (PO 4 ) 3 /C, this composite also exhibits excellent performances in full cells.

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Flower-like assembly of ultrathin nanosheets composed of anatase and bronze TiO embedded in carbon is successfully synthesized by a simple solvothermal reaction, followed with a high-temperature annealing. As an anode material in sodium-ion batteries, this composite exhibits outstanding electrochemical performances. It delivers a reversible capacity of 120 mA h g over 6000 cycles at 10 C. Even at 100 C, there is still a capacity of 104 mA h g. Besides carbon matrix and hierarchical structure, abundant interfaces between anatase and bronze greatly enhance the performance by offering additional sites for reversible Na storage and improving the charge-transfer kinetics. The interface enhancements are confirmed by discharge/charge profiles, rate performances, electrochemical impedance spectra, and first-principle calculations. These results offer a new pathway to upgrade the performances of anode materials in sodium-ion batteries.

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Hierarchically porous NiO microtubes are synthesized by a hightemperature calcination of Ni(dmg) 2 microtubes obtained by a simple precipitation method. The porous NiO microtubes as an anode material for lithium ion batteries exhibit excellent performances, $640 mA h g À1 after 200 cycles at 1 A g À1 .