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The lithium-rich cathode material xLi2MnO3· (1-x) LiMO2 (M=Ni, Co, Mn, etc., 0< x< 1) has the huge advantages of high capacity (up to 300 mA·h/g or more) and low cost, and is known as probably the most important next-generation cathode material for lithium-ion batteries. It has received great attention and extensive research from various countries. At present, this material still has problems such as low initial (first cycle) Coulomb efficiency, poor cycle performance, and serious voltage attenuation, which all seriously hinder the development and practical application of the material. In order to solve these problems of this material, especially its insufficient cycle stability and voltage attenuation, a lot of research work has been carried out on the degradation mechanism and stability improvement of the lithium-rich cathode material, and some important progresses have been made in recent years. This article introduces the structure and working principle of the lithium-rich cathode material, focusing on the research work in recent years on the degradation mechanism of the lithium-rich cathode material and improving the stability of the lithium-rich cathode material. The further research work has been prospected. [ABSTRACT FROM AUTHOR]

Formyldeoxycholic acid modified Fe3O4 nanoparticles (FDCA-MNPs)have been successfully constructed. The structure, morphology and magnetic properties of FDCA-MNPs are characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM)and vibrating sample magnetometer. Oxytetracycline (OTC) is used as a model drug to evaluate the drug loading and release behaviors of FDCA-MNPs. The maximum loading of OTC is 59. 7 mg/g, and the loading behavior follows Freundlich adsorption balance equations with multilayer adsorption．Furthermore, FDCA-MNPs@OTC shows a higher release rate at pH=9 (11. 8%)than that of pH=7 (8. 8%). The bacteriostatic activities of FDCA-MNPs, OTC, FDCA-MNPs@OTC against E. coli are compared in vitro. The results show that FDCA-MNPs have no inhibition-activity for E. coli, meanwhile, FDCA-MNPs@OTC displays better sterilization ability than OTC at the same concentration. The minimum antibacterial concentration is 3 μg/mL, and the antibacterial rate reaches 97. 8%. It is proved that the synergistic effect of drug carrier and drugs reveals good antibacterial properties and reduce the dosage of antibiotics. [ABSTRACT FROM AUTHOR]