can suppress the polysulfide shuttling and exhibit excellent redox electrocatalytic properties for lithium polysulfides decomposition. The batteries with heterostructure-modified separators show a high initial discharge capacity of 1068.4 mAh g −1 at 0.5 C, excellent rate performances (719.6 mAh g −1 at 5C), and a remarkable cycling ability. Even with a high sulfur loading of 6.4 mg cm −2 , the pouch cell can deliver an areal capacity of 5.54 mAh cm −2 at 0.2 C. This work not only provides a new route for preparing SA-catalysts, but also sheds new lights into engineering electronic structures of heterointerfaces for developing high-performance Li-S batteries.

Herein, the amino-capped TiO2 nanoparticles were synthesized using tetrabutyl titanate and amino polymers by a two-step sol-gel and hydrothermal method technique for the fabrication of functional cotton fabric. The prepared TiO2 nanoparticles and the treated cotton fabric were characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), field emission scanning electron microcopy (FE-SEM) photocatalytic and antibacterial measurement. The results indicate the typical characteristic anatase form of the amino-capped TiO2 NPs with an average crystallite size of 14.9 nm. The treated cotton fabrics exhibit excellent antibacterial property and good photocatalytic degradation of methylene blue.

Catalytic chemical degradations and many other methodologies have been explored for the removal and/or degradation of organophosphorus agents (OPs) that are often used as pesticides, nerve agents, and plasticizers. To explore more efficient and recyclable catalysts for the removal and/or degradation of OPs, we fabricate the composites of cobalt nanoparticles and three-dimensional nitrogen-doped graphene (Co/3DNG). We demonstrate that OPs can be hydrolyzed efficiently at ambient temperature by the Co/3DNG. Because of the unique structural and chemical properties of the supporting matrix 3DNG and active species Co−N, the catalytic activities of Co/3DNG composites are much higher than those of bare 3DNG, Co nanoparticles, or the Co nanoparticles physically mixed with 3DNG. We conclude that in the Co/3DNG composites, the interaction between 3DNG and Co stabilizes and distributes well the Co nanoparticles and affords the active catalytic species Co−N.

Gel electrolytes show certain advantages over conventional liquid and solid electrolytes, but their mechanical strength and surface adhesion to the electrode remain to be improved. To address the challenges, we design and fabricate herein the core−shell nanofiber mats in situ on the LiFePO 4 electrode as matrices for gel electrolytes, in which the core is poly(m-phenylene isophthalamide) (PMIA) nanofiber and the shell are composite of Al 2 O 3 nanoparticles and poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP). The mechanical property of the core−shell polymeric nanofiber mats and their surface interaction with LiFePO 4 electrode are characterized complementarily using dynamic thermomechanical analysis and scanning electron microscopy. The electrochemical properties of the gel electrolytes based on the as-prepared matrices after being loaded with lithium salt solution are studied systematically on half coin cells. It is found that the ultimate strength of the core−shell PMIA@PVdF-HFP/Al 2 O 3 mat can reach 6.70 MPa, 2 times higher than that of the PVdF-HFP/Al 2 O 3 nanofiber mat. Meanwhile, the shell PVdF-HFP/Al 2 O 3 can ensure manifest surface affinity to the LiFePO 4 electrode and enhance lithium-ion conductance. Thus, the as-assembled LiFePO 4 half coin cells using PMIA@PVdF-HFP/Al 2 O 3 gel electrolyte show good electrochemical performances, especially the long cycle stability with the capacity retention of 96.6% after 600 cycles under 1C.

The adhesion of a gel electrolyte to the electrode is one of the key factors to the electrochemical performance of lithium-ion batteries (LIBs). Herein, gel electrolyte is prepared on the LiFePO 4 electrode through in situ electrospinning the poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) nanofiber matrix, followed by lithium salt solution loading. The interfacial interactions between the in situ electrospun PVdF-HFP matrix and LiFePO 4 electrode before and after gelation are studied using dynamic thermomechanical analysis and scanning electron microscopy. The results demonstrate that the as-prepared gel electrolyte can adhere tightly onto the LiFePO 4 electrode. LIBs (half coin cells) are assembled using the as-obtained gel electrolyte to evaluate their electrochemical properties. The results show that the lithium-ion and electron transfer rates crossing the interface between gel electrolyte and LiFePO 4 electrode are enhanced. The electrochemical performances of the half coin cells, including specific capacity, rate capability, and cycle stability, are improved significantly.