In this work, superparamagnetic Fe3O4@PPy nanocomposite with core‐shell structure having strong near‐infrared (NIR) absorption is synthesized via a facile two‐step modified procedure. The prepared nanocomposite samples are characterized by UV–vis, FTIR, SEM, TEM, VSM, and XRD. The effects of laser power density (1.5–2.5 W cm−2) and aqueous concentration (0.01–0.2 mg ml−1) of the nanocomposite on the photothermal performance are investigated in the NIR region (808 nm). At 0.1 mg ml−1 concentration, the temperature reaches up to 50.1°C, 64.1°C, and 78.4°C within 10 min, under 1.5 W cm−2, 2.0 W cm−2, and 2.5 W cm−2 NIR laser power density values, respectively. Photothermal conservation efficiency is calculated as 43.9% and the nanocomposite exhibits excellent photothermal stability. In summary, the core‐shell Fe3O4@PPy nanocomposite is a promising candidate for photothermal therapy and simultaneous magnetic field‐guided treatments.

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In this study, graphene oxide‐iron oxide‐polypyrrole (GO‐Fe3O4‐PPy) ternary nanocomposites having high photothermal activity and stability are synthesized and analyzed using ultraviolet–visible (UV–Vis) spectroscopy, Fourier transform infrared (FTIR), X‐ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high‐resolution transmission electron microscopy (HRTEM), and magnetic hysteresis measurement (VSM). The effect of power density (1.5–2.5 W cm−2), concentration (0.01–0.2 mg mL−1), and component composition of nanocomposites on the photothermal properties in the near‐infrared (NIR) region (808 nm) is examined. The results show that superparamagnetic GO‐Fe3O4‐PPy ternary nanocomposite exhibits excellent photothermal performance. The temperature reaches to 55.5, 72.3, and 83.1 °C under the irradiation of the 808 nm NIR laser at 1.5, 2.0—, and 2.5 W cm−2 of power density for 10 min at 0.1 mg mL−1 photothermal therapy (PTT) agent, respectively, and moreover it has excellent photothermal stability. In summary, it is concluded that synthesized nanocomposites potentially may be used in simultaneous magnetic field‐guided treatments. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48837.

In the present study, the green chemistry approach for the biosynthesis of Ag, Au and Ag-Au bimetallic nanoparticles (NPs) was applied using lichen extract [Cetraria islandica (L.) Ach.]. The lichen extract acts both as a reducing and stabilizing agent. The monometallic and bimetallic NPs were characterized by transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The results showed that NPs were successfully synthesized and the prepared structures were generally spherical. The synthesized nanostructures exhibited excellent catalytic activities towards reduction of nitrophenols (4-nitrophenol; 4-NP) to aminophenols (4-aminophenol; 4-AP) with sodium borohydride (NaBH4). It was determined that bimetallic NPs exhibit more effective catalytic activity than monometallic Ag and Au nanostructures. This is the first report on 4-NP reduction with Ag, Au and Au-Ag NP catalysts prepared by lichen extract.

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The aim of this study is to efficiently utilize catalytic properties of silver nanoparticles and nitrogen doped graphene and their combined synergistic effect. For this purpose, nitrogen doped reduced graphene oxide‐silver (NrGO‐Ag) nanocomposites were synthesized by a facile, environmentally friendly, one‐pot hydrothermal method for the first time and characterized by UV–Vis, FTIR, XRD, XPS, SEM, and TEM. Catalytic activity of the synthesized nanocomposites was tested against 4‐nitrophenol (4‐NP) and methylene blue (MB) reduction reactions in the presence of NaBH4. Total degradation was achieved in both reactions in 210 and 44 s, and pseudo first order reaction rate constants were calculated as 0.0071 and 0.0322 s−1 for 4‐NP and MB reduction reactions, respectively.

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