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In this paper, carbon-matrix-supported copper (Cu) and cobaltous oxide (CoO) nanoparticles were obtained by using coordination polymers (CPs) as a precursor. The aqueous solutions of copper methacrylate (CuMA) and cobalt methacrylate (CoMA) were preferentially prepared, which were then mixed with anhydrous ethanol to fabricate dual metal ion coordination polymers (CuMA/CoMA). After calcination under an argon atmosphere, the Cu-CoO/C nanocomposite was obtained. Scanning electron microscope (SEM) and transmission electron microscope (TEM) showed that the material has banded morphology, and the dual functional nanoparticles were highly dispersed in the carbon matrix. The prepared material was used in a heterogeneous Fenton-like reaction, with the aim of replacing traditional ferric catalysts to solve pH constraints and the mass production of ferric slime. The obtained nanocomposite showed excellent catalytic performance on the degradation of methylene blue (MB) at near-neutral conditions; the discoloration efficiency is about 98.5% within 50 min in the presence of 0.15 mmol/mL H2O2 and 0.5 mg/mL catalyst. And good reusability was verified via eight cycles. The plausible pathway for MB discoloration and the possible catalytic mechanism was also proposed. [ABSTRACT FROM AUTHOR]

There are numerous studies about on nanoparticle synthesis by reducing metal salts via bio-extracts. Organic@inorganic hybrid nanoflowers (hNFs), are synthesized with expensive molecules such as enzymes, DNA and proteins. There are few studies for synthesis of hybrid nanoflowers via bio-extracts. However, the use of algae extracts as an organic component and studies on potential applications are very few. For the first time, the algae extract obtained from the brown macroalgae Desmarestia menziesii was used as the organic component of hNFs. Effect of medium pH, and algal extract concentration on morphological characteristic of hNFs were evaluated. The dye degradation and antioxidant activities of hNFs synthesized under optimum conditions were determined. hNFs were not synthesized in the acidic conditions of the PBS buffer (pH 5), The synthesis of hNFs was realized with coordination of Cu+2 and algae extract (0.65, 1, and 1.65 mL) in PBS (pH 7.4 and 9). hNFs with ideal flower morphology (size: 16–19 µm) were obtained by using 1.65 mL of extract under pH 7.4 condition. The basic skeletons (C, O, P, Cu), presence of phosphate crystals (PO4−3) and cristalinity of hNFs were determined by EDX, FT-IR and XRD, respectively. Antioxidant activity of hNFs against DPPH were determined depending on concentration (IC50: 950 µg/ mL). The highest catalytic activities of hNFs against methylene blue and brilliant blue dyes were observed at the mediums of pH 7 (69.81%) and pH 5 (75.7%), respectively. Organic@inorganic hNFs were synthesized by using brown macroalgae D. menziesii depending on extract concentration and medium pH. According to our findings, these hNFs are suitable for using as catalyst and antioxidant agents. [ABSTRACT FROM AUTHOR]