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Self‐activated Ca5Mg3Zn(VO4)6 and Ca5Mg3Zn(VO4)6:xEu3+ phosphors were synthesized via a high‐temperature solid‐state reaction route. The crystalline structure and luminescence properties of the phosphors were analyzed using an X‐ray diffractometer and a photoluminescence spectrometer. The explored results indicated that by varying calcination temperature and the raw material ratio of Ca2+/Mg2+/Zn2+, the phosphors could be developed with different phases, crystallinity, and various fluorescence performances. The fluorescence spectrum of Ca5Mg3Zn(VO4)6 showed a broad emission band over the range 400–650 nm under an excitation wavelength of 330 nm, as well as green light emission. Furthermore, after introduction of Eu3+ ions in Eu(VO4)4, the luminescence intensity of the Eu3+ ions greatly increased as the Eu3+ ion concentration increased at the 393 nm excitation wavelength, showing green–yellow light emission simultaneously. Therefore, the obtained phosphors could be used as a potential green–yellow‐emitting luminescent material in a white light‐emitting diode device. [ABSTRACT FROM AUTHOR]

A facile and scalable route for the in-situ synthesis of porous MnO/C nanocomposite by annealing Mn3(C6H5O7)2 precursor has been developed. MnO particles were encapsulated inside the carbon matrix to form a skeletal architecture. Such a mesoporous structure provided more active sites and effective channels for Li+ and electrolyte, and act as the supporting structure for MnO particles during the cycling process. As an anode material for lithium ion batteries, the porous MnO/C composite had a specific capacity of 831.7 mAh g-1 at 100 mA g-1 and delivered a stable cycling capacity of 564.1 mAh g-1 after 59 cycles, indicating that the porous MnO/C nanocomposite could significantly improve the structural stability and might be a suitable electrode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The applications of ZnO anode material in lithium‐ion batteries are limited due to its large volume changes and low electric conductivity in discharge–charge cycles. In the study, the molecular‐level design is employed to develop a novel ZnO/porous carbon composite structure. With zinc citrate as the precursor, ZnO/porous carbon microspheres self‐assembled by nanosheets are successfully synthesized according to the carbonization method. ZnO particles with the size of 10–30 nm are uniformly dispersed inside porous carbon, which acts as a buffer layer. As the anode material, ZnO/porous carbon microspheres exhibit excellent cycle capacity (557 mAh g−1 at 100 mA g−1) and rate performance (304 mAh g−1 at 1 A g−1). The as‐prepared ZnO/porous carbon microspheres not only guarantee the structural integrity of electrode, but also directly solve the problem of capacity fading. The in situ composite structure may endow ZnO/porous carbon microspheres with wide application potentials in lithium‐ion batteries. The study may also pave a new way to design high‐performance anode materials for lithium‐ion batteries at the molecular scale. Based on molecular‐level design, ZnO/porous carbon microspheres self‐assembled by nanosheets are successfully synthesized using zinc citrate as the precursor. Results indicate that the ZnO/porous carbon microspheres exhibit excellent cycle capacity and rate performance. The in situ composite structure may endow ZnO/porous carbon microspheres with wide application potentials in lithium‐ion batteries. [ABSTRACT FROM AUTHOR]