Black phosphorus (black P), which is a promising candidate as an anode material for lithium-ion batteries, was synthesized by a high-pressure and high-temperature (HPHT) method from white and red phosphorus. The study revealed the electrochemical activity of pure black P under different pressures and temperatures systematically. The sample shows higher crystallinity and purity by the HPHT method. Lithium-ion batteries containing black phosphorus as anode materials exhibited a high specific capacity and excellent cycling performance. Black phosphorus obtained from white phosphorus exhibited the highest first discharge and charge capacities of 2505 and 1354 mAh•g −1 at 4 GPa and 400 °C and that obtained from red phosphorus exhibited the highest first discharge and charge capacities of 2649 and 1425 mAh•g −1 at 4.5 GPa and 800 °C. Black P was characterized by X-ray diffraction, Raman microscopy, scanning electron microscopy, and high-resolution transmission electron microscopy.

Multiporous MnCo2O4 microspheres are fabricated via the solvothermal method followed by pyrolysis of carbonate precursor to demonstrate excellent bifunctional catalytic activity toward both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Because of this multiporous structure, the resulting MnCo2O4 microspheres show an efficient electrocatalytic performance in LiTFSI/TEGDME electrolyte-based Li–O2 batteries. MnCo2O4 microspheres as the air cathode deliver better performance during the discharging and charging processes and good cycle stability compared with that of the Super P. This preliminary result manifests that multiporous MnCo2O4 microspheres are promising cathode catalysts for nonaqueous Li–O2 batteries.

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A superior Na3 V2 (PO4 )3 -based nanocomposite (NVP/C/rGO) has been successfully developed by a facile carbothermal reduction method using one most-common chelator, disodium ethylenediamintetraacetate [Na2 (C10 H16 N2 O8 )], as both sodium and nitrogen-doped carbon sources for the first time. 2D-reduced graphene oxide (rGO) nanosheets are also employed as highly conductive additives to facilitate the electrical conductivity and limit the growth of NVP nanoparticles. When used as the cathode material for sodium-ion batteries, the NVP/C/rGO nanocomposite exhibits the highest discharge capacity, the best high-rate capabilities and prolonged cycling life compared to the pristine NVP and single-carbon-modified NVP/C. Specifically, the 0.1 C discharge capacity delivered by the NVP/C/rGO is 116.8 mAh g(-1) , which is obviously higher than 106 and 112.3 mAh g(-1) for the NVP/C and pristine NVP respectively; it can still deliver a specific capacity of about 80 mAh g(-1) even at a high rate up to 30 C; and its capacity decay is as low as 0.0355 % per cycle when cycled at 0.2 C. Furthermore, the electrochemical impedance spectroscopy was also implemented to compare the electrode kinetics of all three NVP-based cathodes including the apparent Na diffusion coefficients and charge-transfer resistances.