Reinforced polysulfide barrier by g-C_(3)N_(4)/CNT composite towards superior lithium-sulfur batteries

The notorious shuttle effect has long been obstructing lithium-sulfur(Li-S) batteries from yielding the expected high energy density and long lifespan.Herein,we develop a multifunctional polysulfide barrier reinforced by the graphitic carbon nitride/carbon nanotube(g-C_3 N_4/CNT) composite toward inhibited shuttling behavior and improved battery performance.The obtained g-C_3 N_4 delivers a unique spongelike architecture with massive ion transfer pathways and fully exposed active interfaces,while the abundant C-N heteroatomic structures impose strong chemical immobilization toward lithium polysulfides.Combined with the highly conductive agent,the g-C_3 N_4/CNT reinforced separator is endowed with great capability of confining and reutilizing the active sulfur within the cathode,thus contributing to an efficient and stable sulfur electrochemistry.Benefiting from these synergistic attributes,Li-S cells based on g-C_3 N_4/CNT separator exhibit an excellent cyclability with a minimum decay rate of 0.03% per cycle over 500 cycles and decent rate capability up to 2 C.Moreover,a high areal capacity of 7.69 mAh cm^(-2)can be achieved under a raised sulfur loading up to 10.1 mg cm^(-2).demonstrating a facile and efficient pathway toward superior Li-S batteries.

Numerical simulation and parameter optimization of Coriolis force scale measurement process based on DEM

The Coriolis force method is a recently developed and highly regarded direct measurement technique that enables high-precision measurement of bulk materials.The operational parameters and variations thereof directly influence the measurement accuracy of the equipment.In this study,a measurement correction coefficient is introduced to improve the calculation method for mass flow rate of the materials.The DEM is employed to simulate the motion of particle groups within the Coriolis force scale under different parameters,and the effects of various structural and operational parameters on the measurement results are compared.The research findings indicate that a lower rotational speed leads to more stable instantaneous measurement results,although the measurement error is relatively large.When the rotational speed exceeds 300 rpm,the measurement error remains within 15%.For materials with a radius of 1–2 mm,the variation range of precision error is approximately 0.4%.Among the structural parameters,the radius of the measurement wheel has the most significant impact on the measurement results,wherein a larger measurement wheel radius corresponds to a smaller measurement error.The horizontal angle of the blades follows as the next influential parameter,with a clockwise rotation and a horizontal angle of 30°resulting in a measurement error below 2%.

Nickel-decorated TiO2 nanotube arrays as a self-supporting cathode for lithium-sulfur batteries

Lithium-sulfur batteries are considered to be one of the strong competitors to replace lithium-ion batteries due to their large energy density.However,the dissolution of discharge intermediate products to the electrolyte,the volume change and poor electric conductivity of sulfur greatly limit their further commercialization.Herein,we proposed a self-supporting cathode of nickel-decorated TiO2 nanotube arrays(TiO2 NTs@Ni)prepared by an anodization and electrodeposition method.The TiO2 NTs with large specific surface area provide abundant reaction space and fast transmission channels for ions and electrons.Moreover,the introduction of nickel can enhance the electric conductivity and the polysulfide adsorption ability of the cathode.As a result,the TiO2 NTs@Ni-S electrode exhibits significant improvement in cycling and rate performance over TiO2 NTs,and the discharge capacity of the cathode maintains 719 mA·h·g−1 after 100 cycles at 0.1 C.