Electrospinning synthesis of novel lithium-rich 0.4Li2MnO3.0.6LiNi1/3CO1/3Mn1/3O2 nanotube and its electrochemical performance as cathode of lithium-ion battery

In this study, a lithium-rich 0.4Li2MnO3.0.6LiNi1/3Co1/3Mn1/3O2 nanotube layered cathode synthesized by novel electrospinning is reported, and the effects of temperature on the electrochemical performance and morphologies are investigated. The crystal structure is characterized by X-ray diffraction patterns, and refined by two sets of diffraction data （R-3m and C2/m）. Refined crystal structure is 0.4Li2MnO3.0.6LiNi1/3COl/3Mn13O2 compos- ite. The inductively coupled plasma optical emission spec- trometer and thermogravimetric and differential scanning calorimetry analysis measurement supply reference to opti- mize the calcination temperature and heat-treatment time. The morphology is characterized by scanning and high- resolution transmission electron microscope techniques, and the micro-nanostructured hollow tubes of Li-rich 0.4Li2MnO3-0.6LiNil/3COl/3Mn1/3O2 composite with outer diameter of 200-400 nm and the wall thickness of 50-80 nm are synthesized successfully. The electrochemical evaluation shows that 0.4Li2MnO3.0.6LiNi1/3Cov3Mn1/3O2 sintered at 800 ℃ for 8 h delivers the highest capacity of the first dis- charge capacity of 267.7 mAh/g between 2.5 V and 4.8 V at 0.1C and remains 183.3 mAh/g after 50 cycles. The electro- spinning method with heat-treatment to get micro-nanos- tructured lithium-rich cathode shows promising application inlithium-ion batteries with stable electrochemical performance and higher C-rate performance for its shorter Li ions transfer channels and stable designed structure.

Vector soliton and noise-like pulse generation using a Ti3C2 MXene material in a fiber laser

We built a Tm:Ho co-doped fiber laser using a Ti3C2 MXene material as a saturable absorber(SA).The formation of vector solitons(VSs)and noise-like pulses(NLPs)was observed.The SA was prepared by dripping a Ti3C2 solution on a side-polished D-shaped fiber and then naturally vaporized.The VS is characterized by two coexisting sets of Kelly sidebands.By modulating the polarization controller in the fiber laser,NLPs with about 3.3 nm bandwidth can be switched from the VS.To the best of our knowledge,this is the first time that VSs have been generated in a fiber laser using a Ti3C2 MXene material as the SA.