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Biogenic nanoparticles are considered effective alternatives to chemical pesticides for the management of pathogenic plant diseases. This study was focused on the synthesis of stable silver nanoparticles (AgNPs) to control challenging plant pathogenic bacteria in vitro and in planta. We synthesized AgNPs by reacting different proportions of silver nitrate and aqueous extract of Hedera nepalensis. The physicochemical properties of the synthesized AgNPs were determined by using various physical techniques. The TEM analysis revealed the AgNPs less than 50 nm in size and spherical shaped. For antibacterial assays, different concentrations (1000–15.62 µg/mL, 2-fold dilutions) of the extract-free AgNPs (Ef-AgNPs) or extract-mixed AgNPs (Em-AgNPs), and fruit extracts (FE) were used against plant pathogenic bacteria Erwinia carotovora subsp. carotovora, Erwinia carotovora subsp. atroseptica, and Ralstonia solanacearum. In the in vitro assays, we found significant inhibition of both bacterial species in response to maximum concentrations of AgNPs. Overall, Ef-AgNPs exhibited a higher percent inhibition of bacterial pathogens. In potato tubers assay, complete inhibition of Erwinia carotovora was observed, except for the lowest AgNPs concentration of 15.62 µg/mL. Similarly, exposure of tomato plants to Ralstonia solanacearum suspensions (OD600 = 0.2) in the soil-drenching experiment and post-exposure treatment with 1000 µg/mL and 125 µg/mL of AgNPs resulted in disease inhibition. This study provides the basis that biogenic nanoparticles prepared from Hedera nepalensis are one of the best substitutes to synthetic pesticide, having displayed better results to control the growth of phytopathogenic microbes. However, field studies need to be conducted in a controlled environment to scale up the current work and find out the efficacy of nanoparticles on a larger scale. [ABSTRACT FROM AUTHOR]

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Two-dimensional graphitic carbon nitrides (2D g-C3N4) are promising photocatalysts for water splitting to hydrogen due to their non-toxicity and high stability. However, the bulk g-C3N4 has some intrinsic drawbacks, such as rapid electron–hole recombination and low charge-carrier mobility, resulting in poor photocatalytic activity. Here, 2,4-diamine-6-phenyl-1,3,5-triazine was employed as a precursor to regulating the assembly of melamine and cyanuric acid in water. The resulting g-C3N4 not only improved the visible light absorption and electron–hole separation but also provided more catalytic sites for enhanced photocatalytic hydrogen evolution. The modified g-C3N4 (CNP10-H) showed a hydrogen-releasing rate of 2184 μmol·g−1·h−1, much higher than the bulk g-C3N4. [ABSTRACT FROM AUTHOR]

The practical application of lithium-sulfur (Li-S) batteries is hampered by the insulative nature of sulfur, sluggish electrochemical kinetics, and large volume variation, which result in capacity-fading at a large current density and poor cycling stability. Herein, a three-dimensional (3D) aluminum photonic crystal encapsulating sulfur (APC@S) composite as a binder-free cathode for Li-S battery is reported. The 3D APC@S cathode can deliver a fantastic capacity of 1,517.8 mAh·g−1 at 0.5 C, and retains 712.7 mAh·g−1 after 1,500 cycles at 2 C with a decay rate of 0.02% per cycle. Even at a high rate of 5 C, the reversible capacity can still maintain at 680.7 mAh·g−1 after 1,000 cycles with a capacity retention of 74.8%. Furthermore, the assembled soft-packaged Li-S battery also exhibits high reversible capacity and stable cycling performance. The excellent electrochemical performance is attributed to the 3D hierarchical and continuously porous structure and high conductive aluminum-wall, which can effectively trap polysulfides, confine the volume expansion on cycling, and accelerate electron/ion transfer. It is expected that this high conductive metal cathode has a great future for the application of energy storage devices. [ABSTRACT FROM AUTHOR]

Transition metal@nitrogen–carbon (M@NC) catalysts are greatly desired for zinc–air batteries due to the promising oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) properties. Herein, a uniformly distributed Co@NC catalyst derived from metal–organic frameworks is developed. The CoNx species and Co nanoparticles encapsulated in carbon networks promote ORR and OER kinetics synergistically. Moreover, a novel structure is designed for exposing active sites, which consists of 3D macroporous skeleton embedded in carbon fiber paper. It is revealed that the outstanding ORR and OER properties attribute to the sufficient active area obtained from porous structure and ultra‐thickness (280 µm). Besides, interconnected macropores provide abundant channels for mass transport. The liquid ZABs assembled using 3DOMCo@NC‐1‐090 displays outstanding performances. [ABSTRACT FROM AUTHOR]

A novel graphene nanoplatelets (GNP) bridge between two semiconductors (AgBr and graphitic carbon nitride) was created to boost photoelectrochemical performance. The heterojunction created makes the whole system a Z-scheme catalyst. For the construction of this catalyst, the syringe pump methodology was adopted and different analytical techniques were used for the confirmation of structure and morphology. High angle annular dark field (HAADF), dark field (DF), DF-4 and DF-2 techniques, using Z-contrast phenomena, confirmed the heterostructure (ABGCN) and its composition. The constructed structure showed an enhanced photoelectrochemical and catalytic property against 'acute toxicity category-III (MM)' and 'category-IV (tetracycline hydrochloride (TH))' organic pollutants. The constructed catalyst degraded the MM in 57 min and the TH in 35 min with degradation rates of 0.01489 min−1 and 0.02387 min−1, respectively, due to the accumulation of photogenerated electrons on the conduction band (CB) of g-C3N4 and photogenerated holes on the valence band (VB) of AgBr by the transformation of charges through the graphene bridge. An ion trapping study also revealed that ·O2 and h+ were the active species which actively participated in the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

The vacuum tube method has been used for the construction of nondestructive and physically stable graphitic carbon nitride/graphene nanoplatelet composites and their photocatalytic behavior studied by measuring different photoactivities, such as photocurrent, photoluminescence, and the photodegradation of tetracycline hydrochloride under visible‐light irradiation. The formation of a heterojunction was confirmed by XRD, TEM, SEM, FTIR, XPS, and Raman spectroscopy. The results of this research indicate that the vacuum tube method is a facile, economic, and environmentally friendly approach to the preparation of composites. An ion‐trapping experiment indicated that, under visible light, the most effective photocatalyst generated the superoxide radical (O2·–) and holes (h+) to achieve the complete degradation of tetracycline hydrochloride. [ABSTRACT FROM AUTHOR]

Correction for ‘Facile solvothermal synthesis of a high-efficiency CNNs/Ag/AgCl plasmonic photocatalyst’ by Youliang Wang et al., Phys. Chem. Chem. Phys., 2016, DOI: URL10.1039/c6cp04655j/URL. [ABSTRACT FROM AUTHOR]