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    Hydrothermal in situ preparation of phthalocyanine–TiO2 nanocomposites for photocatalytic activity under visible light irradiation
    (Springer Science and Business Media B.V., 2021) Gorduk, Semih; Avciata, Oguzhan; Avciata, Ulvi
    Abstract: In this study, phthalocyanine (Pc)–TiO2 nanocomposites were prepared via in situ hydrothermal method. The metal-free, zinc(II), cobalt(II), nickel(II) and copper(II) Pc compounds were used for formation of nanocomposites. A total of 5 different Pc–TiO2 nanocomposites was successfully prepared by hydrothermal method. The prepared nanocomposites were also characterized by FT-IR, XRD, FEG-SEM, EDX, UV-DRS and BET techniques. All prepared nanocomposites were tested for their photocatalytic activity to be used as photocatalyst. For this purpose, photocatalytic activities of Pc–TiO2 nanocomposites were evaluated for the degradation efficiency of methylene blue (MB) under visible light irradiation by monitoring the UV–Vis absorption spectra. Based on the conducted studies, it was observed that Pc–TiO2 photocatalysts have significant photocatalytic activities on degradation of MB under visible light irradiation, resulting in complete degradation of MB in 100–130 min for full degradation (100%). Furthermore, the reusability studies revealed that photocatalysts show 76% activity even after 5 uses. Graphic abstract: In this study, we prepared and characterized TiO2 nanocomposites using peripherally tetra-substituted metal-free, Zn(II), Co(II), Ni(II) and Cu(II) phthalocyanine complexes. The phthalocyanine–TiO2 nanocomposites showed significant photocatalytic activities for cleaning a common organic pollutant under the visible light irradiation.[Figure not available: see fulltext.] © 2020, Springer Nature B.V.
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    Synthesis of Peripherally Tetrasubstituted Phthalocyanines and Their Applications in Schottky Barrier Diodes
    (Hindawi Limited, 2017) Gorduk, Semih; Koyun, Ozge; Avciata, Oguzhan; Altindal, Ahmet; Avciata, Ulvi
    New metal-free and metallophthalocyanine compounds (Zn, Co, Ni, and Cu) were synthesized using 2-hydroxymethyl-1,4-benzodioxan and 4-nitrophthalonitrile compounds. All newly synthesized compounds were characterized by elemental analysis, FT-IR, UV-Vis, 1H-NMR, MALDI-TOF MS, and GC-MS techniques. The applications of synthesized compounds in Schottky barrier diodes were investigated. Ag/Pc/p-Si structures were fabricated and charge transport mechanism in these devices was investigated using dc technique. It was observed from the analysis of the experimental results that the charge transport can be described by Ohmic conduction at low values of the reverse bias. On the other hand, the voltage dependence of the measured current for high values of the applied reverse bias indicated that space charge limited conduction is the dominant mechanism responsible for dc conduction. From the observed voltage dependence of the current density under forward bias conditions, it has been concluded that the charge transport is dominated by Poole-Frenkel emission. © 2017 Semih Gorduk et al.