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The "shuttle effect" of long-chain polysulfides and the low conductivity of elemental sulfur lead to the inferior cycling stability of lithium–sulfur batteries and imped their practical applications. Herein, Co3O4 nanoflakes with uniform macro pores distribution were synthesized via facile oil bath and calcination methods. Coupled with super P and coated on common polypropylene separators, they were expected to hinder the migration of lithium polysulfides (LiPSs) and accelerate the redox kinetics of polysulfides. Coin cells assembled with the Co3O4–super P interlayer exhibited a capacity of 760 mA h g−1 at 1 C, maintained 598 mA h g−1 after 350 cycles, and the decay rate of discharge capacity was only about 0.062% per cycle. Such high performance can be attributed to the synergistic effects between polar Co3O4 and conductive super P. The facile fabrication method and high performance make the Co3O4-super P interlayer a feasible material to apply in lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

MoO3−x nanobelts with different concentrations of oxygen vacancies were synthesized by a one-step hydrothermal process. XPS test results show that oxygen vacancies are distributed from the exterior to the interior of the MoO3−x nanobelts. As an anode material for lithium-ion batteries, MoO3−x-10 releases excellent rate capacitance. It can maintain a high specific capacitance of about 500 mA h·g−1 at a high current density of 1000 mA·g−1. In the aspect of cycling stability, MoO3−x-10 can retain a high specific capacity of 641 mA h·g−1 after cycling for 50 times at 100 mA·g−1 and 420 mA h·g−1 after cycling for 100 times at 500 mA·g−1. The coexistence of oxygen vacancies and low-valence Mo ions is conducive to the intercalation/de-intercalation of Li ions and to promoting redox reactions. It has been proved to be a significantly effective way in which oxygen vacancies can improve the integrated performance of MoO3−x nanobelts as anode materials. [ABSTRACT FROM AUTHOR]