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    Catalytic hydrogen evolution by molybdenum-based ternary metal sulfide nanoparticles
    (American Chemical Society, 2019) Aslan, E.; Sarılmaz, Adem; Özel, Faruk; Hatay, Patir I.; Girault, H.H.
    The search for highly active earth-abundant elements and nonexpensive catalysts for hydrogen evolution reaction is a vital and demanding task to minimize energy consumption. Transition metals incorporated into molybdenum sulfides are promising candidates for hydrogen evolution because of their unique chemical and physical properties. Here, we first describe a general strategy for the synthesis of particle-shaped molybdenum-based ternary refractory metal sulfides (MMoSx; M = Fe, Co, Ni, and Mn) through a simple hot-injection method. The newly developed materials are affirmed as valuable alternatives to noble-metal platinum because of their simple fabrication, inexpensiveness, and impressive catalytic performance. We present highly efficient catalysts for hydrogen evolution at a polarized water/1,2-dichloroethane interface by using decamethylferrocene (DMFc). The kinetics of hydrogen evolution studies are monitored by two-phase reactions using UV-vis spectroscopy and also further proven by gas chromotography. These ternary refractory metal sulfide catalysts show high catalytic activities upon hydrogen evolution comparable to platinum. The rate of hydrogen evolution for the MMoSx catalysts changed in the order Ni > Co > Fe > Mn according to the types of first-row transition metals.
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    Donor-p-acceptor dye-sensitized photoelectrochemical and photocatalytic hydrogen evolution by using Cu2WS4 co-catalyst
    (Elsevier Ltd, 2019) Patir, I.H.; Aslan, E.; Yanalak, G.; Karaman, M.; Sarılmaz, Adem; Can, M.; Özel, Faruk
    Photoelectrochemical and photocatalytic hydrogen evolution reaction (HER) have been investigated by using metal free donor-acceptor (D-A) and donor-?-acceptor (D-?-A) dyes, which are abbreviated as MC-32 and MC-048, respectively, sensitized TiO 2 as a photocatalyst with or without Cu 2 WS 4 co-catalyst. This co-catalyst is synthesized by a low-cost and simple hot injection method, under visible light illumination. The photoactivities of these dyes have been clarified according to their structural, optical and electrochemical properties. Photocatalytic activities have been slightly increased when added the Cu 2 WS 4 co-catalyst (dye/TiO 2 /Cu 2 WS 4 ). This catalytic activity is also compared to that of noble metal Pt (dye/TiO 2 /Pt). It has been found that 121 ?molg ?1 h ?1 , 179 ?molg ?1 h ?1 , 348 ?molg ?1 h ?1 , 212 ?molg ?1 h ?1 , 422 ?molg ?1 h ?1 and 1139 ?molg ?1 h ?1 hydrogen have been evolved by using MC-32/TiO 2 , MC-32/TiO 2 /Cu 2 WS 4 , MC-32/TiO 2 /Pt, MC-048/TiO 2 , MC-048/TiO 2 /Cu 2 WS 4 and MC-048/TiO 2 /Pt, respectively.
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    Hydrogen evolution catalyzed by cu 2 ws 4 at liquid–liquid interfaces
    (American Chemical Society, 2016) Özel, Faruk; Aslan, E.; Sarılmaz, Adem; Hatay, Patır İmren
    The present study reports, for the first time, both a facile synthesis for ternary Cu 2 WS 4 nanocubes, which were synthesized by a simple and low-cost hot-injection method, and the hydrogen evolution reaction at a biomembrane-like polarized water/1,2-dichloroethane interface catalyzed by Cu 2 WS 4 nanocubes. The rate of hydrogen evolution reaction is increased by about 1000 times by using Cu 2 WS 4 nanocubes when compared to an uncatalyzed reaction. © 2016 American Chemical Society.
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    The investigation of novel D-?-A type dyes (MK-3 and MK-4) for visible light driven photochemical hydrogen evolution
    (Elsevier Ltd, 2019) Aslan, E.; Karaman, M.; Yanalak, G.; Can, M.; Özel, Faruk; Patir, I.H.
    Two novel donor-?-acceptor (D-?-A) semiconductor organic dyes have been synthesized for the photochemical hydrogen evolution reaction (HER) to sensitize TiO2 for the first time. The molecular structures of D-?-A semiconductor organic dyes, which are entitled as MK-3 and MK-4, have been characterized by NMR spectroscopy method; and also electrochemical and optical properties have been investigated by cyclic voltammetry and UV–Vis absorption techniques, respectively. Amount of dye loading on TiO2 surface has been investigated by EDX method. The HER activities have been explored in the presence of triethanolamine (TEOA) as a electron donor reagent under sunlight (solar simulator illumination limited by cut-off filter ? ? 420 nm) in the absence and presence of co-catalysts (Pt and Cu2WS4). Transient photocurrent densities of MK-3/TiO2 and MK-4/TiO2 electrodes have been reached to 110 ?A cm?1 and 275 ?A cm?1, respectively. The photocatalytic HER activities have been relatively enhanced in the presence of the Pt or Cu2WS4 co-catalysts (dye/TiO2/Cu2WS4 or dye/TiO2/Pt) when compared to only dye/TiO2. The HER rates have been found as 427, 1277, 675, 682, 1027 and 795 ?molg?1h?1 for the MK-3/TiO2, MK-3/TiO2/Pt, MK-3/TiO2/Cu2WS4, MK-4/TiO2, MK-4/TiO2/Pt and MK-4/TiO2/Cu2WS4, respectively. The differences of photochemical activities of MK-3/TiO2 and MK-4/TiO2 have been stated taking into account dye molecule structures. Moreover, the HER mechanism have been described by using electrochemical band energy levels of dyes, TiO2 and Cu2WS4 co-catalyst.
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    Photocatalytic H 2 evolution with a Cu 2 WS 4 catalyst on a metal free D-?-A organic dye-sensitized TiO 2
    (Elsevier B.V., 2017) Aslan, E.; Gönce, M.K.; Yiğit, M.Z.; Sarılmaz, Adem; Stathatos E.; Özel, Faruk; Can, M.
    A system comprising of a noble metal free Cu 2 WS 4 catalyst and donor-?-bridge-acceptor metal-free organic dyes (MZ-341 and MZ-235) sensitized TiO 2 has been reported for the photocatalytic hydrogen production using triethanolamine (TEOA) as the sacrificial reagent under visible light irradiation. Cu 2 WS 4 nanocubes were synthesized according to hot-injection reaction technique. The structural properties of the Cu 2 WS 4 nanocubes were examined by microscopy (HR-TEM) and XRD techniques where the formation of nanocubes (rectangular and square cubes) with average edge length to be ranged from 100 to 500 nm and tetragonal phase (I-42m) was proved respectively. It was found that MZ-341 and MZ-235 dyes sensitized TiO 2 have been produced 661 ?mol g ?1  h ?1 and 531 ?mol g ?1  h ?1 hydrogen, respectively in TEOA solution at pH 9. When Cu 2 WS 4 , was used as a co-catalyst, hydrogen evolution by MZ-341 and MZ-235 sensitized TiO 2 have been slightly increased to 1406 ?mol g ?1  h ?1 and 943 ?mol g ?1  h ?1 , respectively. © 2017 Elsevier B.V.
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    Short-term diabetes causes cardiovascular inflammation: anti-inflammatory effect of resveratrol
    (Wiley-Blackwell, 2016) Koca, H. B.; Sadi, Gökhan; Pektaş, A.; Pektaş, M. B.; Aslan, E.; Koca, S.; Tosun, M.
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    Ternary and quaternary thiospinel nanocrystals with adjustable compositions: effects of Band-Gaps and nanostructures on Visible-Light-Driven photocatalytic H-2 evolution
    (Elsevier, 2020) Sarılmaz, Adem; Yanalak, Gizem; Aslan, E.; Akyıldız, Hasan; Patır, İmren H.; Özel, Faruk
    Ternary and quaternary structured thiospinel nanocrystals are important materials for energy applications based on their outstanding characteristics such as earth abundant components, non-toxic nature and simple production. In this study, CuNiCoS4, CuCo5S8 and CuCo2S4 nanocrystals have been successfully synthesized via hot injection-method with generalized synthesis conditions and detailed structural, optical and electrochemical characterizations were performed for the first time. The characterization results indicated that the nanocrystals were single phase, nearly stoichiometric composition and a mean size below 10 nm. Moreover, the synthesized nanocrystals have been used for the photocatalytic hydrogen evolution as a catalyst under visible light irradiation. In these reactions, CuNiCoS4 nanocrystals exhibited higher photocatalytic activity and stability than the others. CuNiCoS4 and CuCo5S8 catalyst have firstly been proven as valuable alternatives to CuCo2S4 structure and Platinum in hydrogen evolution reactions and are of particular interest due to lower costs, ease of fabrication and comparable evolution performance.
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    Transition metaleincorporated tungsten-based ternary refractory metal selenides (MWSex; M = Fe, Co, Ni, and Mn) as hydrogen evolution catalysts at soft interfaces
    (Elsevier, 2020) Aslan, E.; Sarılmaz, Adem; Yanalak, G.; Özel, Sultan Süleyman; Özel, Faruk; Patir, I. H.
    Hydrogen evolution reaction (HER) catalysts including transition metal chalcogenides have been recognized as a class of very promising non-expensive and earth-abundant catalysts. Tremendous investigations on the binary and ternary metal sulfides/selenides have demonstrated extraordinary chemical and physical properties such as good structural stability and adjustable chemical composition. The ternary amorphous refractory metal selenides (MWSex; M = Fe, Co, Ni, Mn) have been synthesized by the hot-injection method. The NiWSex, CoWSex, FeWSex and MnWSex nanostructures have been used as catalysts for the hydrogen evolution at the biphasic systems of water and 1,2-dichloroethane with similar to a biomembrane. The catalytic activity differences of ternary metal selenides have been compared with each other taking into account transition metals which are changed in the order of Fe approximate to Mn << Co < Ni. The catalytic activities of the MWSex have not been changed when adding of Fe and Mn into the tungsten selenide nanostructure, which may be originated from amorphous structures of FeWSex and MnWSex. Ni and Co addition into the tungsten selenide have improved the electrocatalytic HER activity when compared with only WSex.