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Highlights: Defect engineering for constructing Zn2+ reservoir to anchor anions. The quasi-solid electrolyte interphase as Zn2+ reservoir boosting charge and mass transfer for dendrite-free zinc battery. A Coulombic efficiency of 99.8% was achieved in Zn||Cu cell. The practical applications of zinc metal batteries are plagued by the dendritic propagation of its metal anodes due to the limited transfer rate of charge and mass at the electrode/electrolyte interphase. To enhance the reversibility of Zn metal, a quasi-solid interphase composed by defective metal–organic framework (MOF) nanoparticles (D-UiO-66) and two kinds of zinc salts electrolytes is fabricated on the Zn surface served as a zinc ions reservoir. Particularly, anions in the aqueous electrolytes could be spontaneously anchored onto the Lewis acidic sites in defective MOF channels. With the synergistic effect between the MOF channels and the anchored anions, Zn2+ transport is prompted significantly. Simultaneously, such quasi-solid interphase boost charge and mass transfer of Zn2+, leading to a high zinc transference number, good ionic conductivity, and high Zn2+ concentration near the anode, which mitigates Zn dendrite growth obviously. Encouragingly, unprecedented average coulombic efficiency of 99.8% is achieved in the Zn||Cu cell with the proposed quasi-solid interphase. The cycling performance of D-UiO-66@Zn||MnO2 (~ 92.9% capacity retention after 2000 cycles) and D-UiO-66@Zn||NH4V4O10 (~ 84.0% capacity retention after 800 cycles) prove the feasibility of the quasi-solid interphase. [ABSTRACT FROM AUTHOR]

Few-layered MoSe2 nanosheets with mixed 1T/2H phase were successfully arrayed on a Ti substrate (forming 1T@2H-MoSe2/Ti) through a facile one-step solvothermal process. After testing different synthesis conditions, it was found that the optimal process involves a temperature of 200 °C and a reaction time of 12 h. Structural characterizations reveal that the morphology of 1T@2H-MoSe2 consists of edge-terminated nanosheets with one to five layers, composed of a mixed 1T/2H phase dominated by the 1T one. The 1T@2H-MoSe2/Ti electrode shows excellent HER catalytic activity, with a small onset potential (−120 mV vs. reversible hydrogen electrode, RHE) and an electrode potential of only −133 mV (vs. RHE) to achieve a current density of 20 mA·cm−2. This excellent electrocatalytic activity is due to the synergistic effects of 1T metallic phase, few-layered nanosheet morphology, and direct growth of 1T@2H-MoSe2on the Ti substrate. In addition, the 1T@2H-MoSe2/Ti electrode shows excellent stability towards long-term electrolysis. This is due to the long-term stability of the valence states of Mo and Se, as shown by post-electrolysis X-ray photoelectron spectroscopy analysis. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) nickel oxide (NiO) catalytic electrode was fabricated by annealing Ni(L-asp)bipy MOF membrane and was subsequently applied for electrochemical glucose sensor. This 3D self-supported MOF membrane precursor provided uniform and porous architecture, and it was used for fabricating 3D NiO electrode in the first time. The SEM and XRD data showed that the NiO was evenly distributed on Ni mesh and complete transformation from Ni(L-asp)bipy to NiO. This catalytic electrode, using a chronoamperometric approach, demonstrated linear range up to 400 μM with high sensitivity of 478.9 μA mM cm and low limit of detection of 4.34 μM. Uric acid, urea and ascorbic acid showed negligible interferences to the detection of glucose. The excellent performance of this electrode was attributed to the uniformly distributed NiO on the Ni substrate, direct electron transformation from Ni substrate to electrochemical active NiO and the porosity of such electrode design. [ABSTRACT FROM AUTHOR]

In this study, adventitious roots of Helicteres angustifolia L. (H. angustifolia) were generated on Murashige and Skoog salt mixture (MS) medium with auxin and ascorbic acid as additives. The root initiation ratio reached 100% on MS medium supplemented with 3.0 mg/L NAA and 0.4 mg/L ascorbic acid at 28 °C. The root number reached 15 ± 2 per leaf explant with a length of 1.70 ± 0.52 cm. Moreover, the cultured roots exhibited similar functional groups with wild plant roots and produced abundant classes of phenolic secondary metabolites. The contents of total phenolics and flavonoids of the cultured roots reached 9.68 mg GAE/g and 25.66 mg RE/g, respectively. Compared to the wild plant roots, the cultured roots produced more gallic acid (1.97 ± 0.09 mg/g), catechol (0.17 ± 0.00 mg/g), caffeic acid (0.34 ± 0.01 mg/g), and quercetin (0.84 ± 0.02 mg/g). Additionally, the adventitious root extract showed dose-dependent antioxidant capability (IC50 of DPPH = 4.10 ± 0.27 mg/mL, IC50 of hydroxyl = 1.59 ± 0.07 mg/mL) and inhibition activities on rat intestinal maltase and sucrase (IC50 of maltase = 5.66 ± 0.20 mg/mL, IC50 of sucrase > 8.0 mg/mL). The adventitious root cultures are promising alternatives to produce bioactive phenolic compounds and functional foods of H. angustifolia. [ABSTRACT FROM AUTHOR]