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The exploration of appropriate layered vanadium-based cathode materials (Zn2+-host) is a crucial and important task for the exploitation of high-performance aqueous zinc ion batteries (AZIBs). Unfortunately, these materials suffer from sluggish kinetics of Zn2+ diffusion and the dissolution of vanadium that make them difficult to reach high capacity and long cycle life. Herein, a novel free-standing cathode (denoted as 3D-NPG@S-NVO@CTAB) has been fabricated by hydrothermal growth of sulfur-doped (NH 4) 2 V 10 O 25 ∙8 H 2 O (S-NVO) hollow nanoflowers in three-dimensional nitrogen-doped porous graphene (3D-NPG) and subsequent C 19 H 42 N+ (CTAB) pre-insertion. Benefitting from the rational design strategy, the oxygen vacancies induced by sulfur doping weaken electrostatic interaction between Zn2+ and cathode, provide more transfer channels and strengthen electronic conductivity. Meanwhile, the simultaneous introduction of S and CTAB into NVO jointly expands interlayer spacing and enhances Zn2+ diffusion kinetics, which suppresses the dissolution of vanadium by reducing water molecule intercalation and maintains the structure integrity with excellent electrochemical performance (525 mAh g−1 at 0.5 A g−1). Even at a high rate of 5 A g−1, the hierarchical cathode (3D-NPG@S-NVO@CTAB) can still deliver a capacity of 356 mAh g−1 with capacity retention rate of 90% after 2000 cycles. Density functional theory (DFT) calculations indicate that S-doping, the introduction oxygen defects and CTAB obviously strengthen carrier concentration, which represents the enhancement of conductivity. This work can provides ideas for the construction of advanced AZIB devices through the inorganic/organic hybridization of vanadium-based electrode materials. [Display omitted] • The self-supporting electrode with oxygen defects and expanded spacing displays excellent electrochemical performance. • The oxygen vacancies induced by sulfur doping weak electrostatic interaction and provide more transfer channels. • CTAB can suppress the dissolution of vanadium with reducing the entry of H 2 O and maintaining the structural stability. • The 3D substrate can prevent the aggregation of materials and avoid the use of binders and conductive additives. [ABSTRACT FROM AUTHOR]

A novel AgO-CoO-CdO/Poly(alanine)-chitosan-reduced graphene oxide (PACSGO) nanocomposite was developed to study the degradation efficiency under visible light irradiation. The AgO, CoO, CdO nanoparticles and AgO-CoO-CdO heterometal oxides were prepared by using the chemical method. The crystallite structure and phase studies were studied by the X-ray diffraction assay. The SEM images were evaluated to explore the morphology of the prepared materials. EDS analysis and FTIR spectra confirmed the formation of nano-materials with high purity. The optical bandgap values were measured via Kubelka-Munk plot showing that the metal oxides produced a new energy state in the electronic level for high photocatalysis efficiency. The incorporation of AgO-CoO-CdO in PACSGO showed a novel nano-photocatalyst for substantial degradation of dye in low process time. The catalysis data displayed that PACSGO based AgO-CoO-CdO nanocomposites ensured a strong potential to degradation of organic dye compounds from water in during photocatalysis reaction. The beneficial anti-pathogenic bacterial performance of the AgO-CoO-CdO/PACSGO nanocomposites was further demonstrated by a substantial reduction in the amount of Staphylococcus aureus , Escherichia coli , Pseudomonas aeruginosa, and B. cereus medium and increase in inhibition zone value with the addition of the AgO-CoO-CdO/PACSGO nanocomposites. [ABSTRACT FROM AUTHOR]

• Design and fabrication of self-assembled Ni-doped ZIF-67 (NiCo-ZIF-67). • Sandwich MXene/NiCoZDHis used for supercapacitor for the first time. • The specific capacitance of MXene/NiCoZDH is greater than that of MXene and ZIF-67. • Excellent cyclic stability of MXene/NiCoZDH (90.9%@30,000). Zeolite-imidazole frameworks (ZIFs) are the promising materials for supercapacitors (SC), however, the shortcomings of easy agglomeration, low conductivity and low stability limit the further improvement of their electrochemical properties. Hence, in order to produce high-performance SC, ZIFs are usually grown directly on some conductive substrates or post-treated. In this paper, MXene was explored as the substrate and Ni-doped ZIF-67 (denoted as NiCo-ZIF-67) was in situ anchored on negatively charged MXene surface via chemical bonds to supply more available active sites for the enhancement of capacitance. At the same time, the surface functional groups in MXene can also enhance the chemical connection between NiCo-ZIF-67 and MXene to attain higher ion diffusion and charge transfer rates. The size of the NiCoZDH (ZIFs-derived double hydroxide denoted as ZDH) obtained by the alkali treatment of NiCo-ZIF-67 is smaller, which is good for increasing specific surface area. The prepared composite MXene/NiCoZDH electrode shows a larger specific capacitance (877 F g-1) than MXene/NiCo-ZIF-67 (460 F·g-1), NiCoZDH (354 F g-1), NiCo-ZIF-67 (130 F g-1) and MXene (15 F g-1), and superior cycling stability with a capacitance retention of 90.9% after 30000 cycles. Additionally, the assembled asymmetric supercapacitor delivers an energy density of 34 Wh kg-1 at the power density of 748 W kg-1 and maintains 93.3% of the initial capacitance after 30,000 cycles. [ABSTRACT FROM AUTHOR]

To satisfy the ever-increasing demand of smart and miniaturized portable devices, supercapacitors have attracted tremendous attention owing to their short charging time, long cycling lifespan, and reliable safety. Nevertheless, the energy density of pseudocapacitors is the major obstacle because of its kinetically sluggish reactions, low mass loading of active materials, and/or high internal resistance. Herein we develop a one-pot hydrothermal method to synthesize NiSe nanorod arrays on nickel foam (NiSe NRA/NF), which exhibit ultrahigh areal capacitance of 6.81 F cm −2 at current density of 5 mA cm −2 as well as excellent cycling stability. The superior performance of NiSe NRA/NF can be attributed to metallic conductivity of nickel selenides, short diffusion length of ions from electrolyte to electrode materials, and fast electrons transport pathway between active materials and current collectors. For practical applications, an asymmetric supercapacitor was assembled by applying NiSe as positive electrode and reduced graphene oxide as negative electrode, delivering an energy density of 38.8 Wh kg −1 at a power density of 629 W kg −1 and 6.38 Wh kg −1 at a power density of 13.5 kW kg −1 . Moreover, the devices retained 90.09% after 3000 cycles at high current density of 3.6 A g −1 , showing a promising application prospect. [ABSTRACT FROM AUTHOR]

A metal porous carbon (Ni@NC) supported nickel/cobalt layered double hydroxide (NiCo-LDH) (Ni@NC@NiCo-LDH) with a cauliflower morphology was synthesized by a successive double template method. At first a nickel metal-organic framework (Ni-MOF) was prepared and used as a sacrifice template to produce metal porous carbon (Ni@NC). Then the prepared conductive porous carbon material was exploited as a substrate for in-situ growing of ZIF-67 on its surface. Lastly the obtained Ni@NC@ZIF-67 was further used as a sacrifice template to prepare the final electrode material Ni@NC@NiCo-LDH by Ni2+ etching and co-precipitation. The cooperation of Ni@NC with excellent conductivity and NiCo-LDH with superior pseudocapacitive property yielded a synergistic effect, which effectively improved the electrochemical performance of the resulted electrode material. And the special flower morphology exposed more redox active sites and provided proper charge transport path for enhanced electrochemical performance. The prepared Ni@NC@NiCo-LDH exhibited a high specific capacitance of 1761.8 F·g−1 at the current density of 1 A·g−1. The assembled Ni@NC@NiCo-LDH//AC asymmetric supercapacitor also displayed an acceptable energy density (39.27 Wh·kg−1 at the power density of 757.21 W·kg−1) and ultrahigh cycling stability (94.74% capacitance retention after 25000 cycles at 10 A g−1). [Display omitted] • Ni@NC@NiCo-LDH was prepared by combination of Ni@NC and NiCo-LDH for the first time. • Ni@NC@NiCo-LDH had a big specific capacitance. • The assembled supercapacitor with Ni@NC@NiCo-LDH and AC had excellent cycle stability. [ABSTRACT FROM AUTHOR]

The application of MOF materials in supercapacitors has been greatly restricted due to the poor conductivity and structural stability. Given that, this work improves the conductivity and stability of Ni-MOF by self-assembled strategy. We report here the Mo-doped Ni-MOF nanosheets (M-NMN), in which the Mo-based clusters are encapsulated in the holes of the Ni-MOF frame structure by self-assembly. The results show that the M-NMN-1 material with a Mi/Mo molar ratio of 1: 1 exhibits an excellent electrochemical performance. Furthermore, the nanosheet structure of the M-NMN-1 materials acts as a "superhigh way" for charge transport to accelerate charge transfer rate and enhance the conductivity of the electrode materials. As-prepared M-NMN-1 electrode material exhibits high specific capacity of 802 C g−1 at 1 A g−1. Furthermore, assembled battery-supercapacitor hybrid device exhibits an excellent energy density of 59 Wh kg−1 at a power density of 802 W kg−1, and superior cycle retention of 93% after 20,000 cycles. Image 1 • Design and fabrication of self-assembled Mo-doped Ni-MOF nanosheets (M-NMN-1). • The M-NMN-1 material exhibits the improved the conductivity and stability. • The ultrahigh specific capacity of 802 C g-1 at 1 A g-1 in three electrode system. • High energy density of 59 Wh kg-1 at power density of 802 W kg-1 in hybrid device. [ABSTRACT FROM AUTHOR]

• ASP alleviated LPS-induced CP progression both in gingival tissue and in PDLCs. • TLR4 mediated LPS-induced CP progression through the TLR4/NF-κB signaling pathway. • Overexpression of TLR4 blocked the protective effect of ASP in LPS-induced CP. The mechanism underlying lipopolysaccharide (LPS)-induced primary human periodontal ligament (PDLC) cell injury is unclear. In this study, we focused on the therapeutic function of asperuloside (ASP) on LPS-induced cell injury. The study enrolled 41 participants, including 18 healthy controls and 23 CP patients. Western blotting was used to measure the expression of Toll-like receptor 4 (TLR4), phosphorylated p65 (p-p65) and cyclin D1. Enzyme-linked immunosorbent assays (ELISAs) were utilized to evaluate the protein levels of proinflammatory factors interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor alpha (TNF-α). MTT assays and 5-ethynyl-2′-deoxyuridine (EdU) staining were performed to investigate cell proliferation. Immunohistochemistry was used to detect TLR4 and p65 expression in gingival tissues. Asperuloside ameliorates lipopolysaccharide-induced PDLC cell injury by decreasing TLR4 expression and NF-κB activation, while this protective effect of ASP was reversed by TLR4 overexpression. [ABSTRACT FROM AUTHOR]