Ag(2)O particles with different polyhedral shapes including octahedron, truncated octahedron, and cube were successfully synthesized by a simple wet-chemical method using silver nitrate, ammonia, and sodium hydroxide as raw materials at room temperature. Simply by tuning the concentration of starting materials, the shape of Ag(2)O particles evolved from octahedron to cube, and the size gradually decreased from 1-2 microm to 400-700 nm. As examples for promising applications, the antibacterial activities of the as-prepared Ag(2)O polyhedral particles were preliminarily studied. It has been found the antibacterial activity of Ag(2)O particles against E. coli depends on the shape of Ag(2)O particles, demonstrating that the surface structure of Ag(2)O particles affects the antibacterial activity.

Soybean [Glycine max (L.) Merr.] stalk-based biochar was prepared using oxygen-limited pyrolysis. We evaluated phenanthrene (PHE) and Hg(II) sorption, from single and binary component solutions, onto prepared biochar. We found that the prepared biochar efficiently removed PHE and Hg(II) from aqueous solutions. The isotherms for PHE and Hg(II) sorption could be described using linear and Tóth models, respectively, both with high regression coefficients (R(2) > 0.995). When PHE and Hg(II) coexisted in an aqueous solution, we observed direct competitive sorption, each one suppressing another. Our results provide insight into the recycling of agricultural residues, and also a new application for removal of polycyclic aromatic hydrocarbons and heavy metals from contaminated water utilizing biochar from agricultural residue.

In this paper, a study on the removal of imitated polystyrene (PS) microplastics in water was carried out based on the adsorption capacity of three-dimensional reduced graphene oxide (3D RGO). Scanning electron microscopy and X-ray diffractometry characterization showed that the freeze-dried 3D RGO formed a distinct porous spatial structure. Different experimental parameters, such as pH, ion concentration (C0), contact time (t), and temperature (T), were studied to investigate the PS microplastic adsorption performance of 3D RGO. The adsorption mechanism was mainly attributed to the strong π–π interaction between the carbon ring of 3D RGO and the benzene ring of PS microplastics. Sorption kinetic and isothermal data were obtained by the well-fitted Langmuir adsorption isotherm model and pseudo-second-order kinetic model. Furthermore, the result of thermodynamic analysis showed that the adsorption of PS microplastics was a spontaneous endothermic process. Under the optimal conditions of pH = 6, C0 = 600 mg/L, t = 120 min, and T = 26 °C, the maximum adsorption capacity of the prepared 3D RGO on PS microplastics was 617.28 mg/g. Furthermore, this method exhibited good feasibility in tap water and lake water.

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