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The real application of lithium-ion batteries in electric vehicles lacks the ideal anode materials. Herein, we report both experimental and theoretical study of MoSe2 nanocrystals as the anode materials. MoSe2 nanocrystals are successfully synthesized via a facile thermal-decomposition process. As the anode, the nanocrystalline MoSe2 yields the initial discharge and charge capacities of 782 and 600 mA h g–1 at the current of 0.1 C in a voltage of 0.1–3 V. First-principles simulation demonstrates that, during the initial discharge process, there is a Li atoms induced phase transition from 2H-MoSe2 to the O-MoSe2 phase at 0.9 V, and then Mo cluster occurs as more Li atoms intercalated into the MoSe2 lattice, which is associated with the formation of Mo and Li2Se. And the following charge/discharge processes are related to the conversion reaction between Mo and Li2Se. Meanwhile, the Li ion vacancy-hopping diffusion mechanism from octahedron to tetrahedron in MoSe2 lattice is proposed based on a quasi-2D energy favorable trajectory and the calculated diffusion constant is 1.31 × 10–13 cm2 s–1. For comparison, the amorphous MoSe2 demonstrates the same phase transition process after the initial charge/discharge cycle. The results show that the nanocrystalline MoSe2 can be the very promising novel anode materials for high performance Li-ion batteries.

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The incorporation of colloidal CdTe quantum dots into an inorganic matrix, BaSO 4 , through a handy and rapid co-precipitation method is demonstrated for the first time. Owing to the protection of the BaSO 4 matrix, the resulting composites show stronger luminescence, longer fluorescent lifetime, and higher photo-and thermal stability as well as being more anti-acid compared to the parental CdTe QDs.Moreover, the composites hold several advantages for industrial applications. White light-emitting diodes (WLEDs) utilizing the composites as a red color conversion layer are fabricated, and produce bright white light with high color-rendering properties including a CIE coordinate of (0.34, 0.33), an R a of 88, and a T c of 5112 K at 20 mA, suggesting their great potential application in a solid-state lighting system with high color-rendering properties.