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" Chalcogenides in Photoelectrochemical Hydrogen Production Application and Characterization "
Ayaz, Rana Muhammad Zunaın
Koca, Atıf
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Latin Dissertation
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English
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| Record Number
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1108587
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TLpq2466888678
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| Main Entry
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Ayaz, Rana Muhammad Zunaın
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Koca, Atıf
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| Title & Author
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Chalcogenides in Photoelectrochemical Hydrogen Production Application and Characterization\ Ayaz, Rana Muhammad ZunaınKoca, Atıf
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| College
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Marmara Universitesi (Turkey)
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| Date
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2019
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2019
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| Degree
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Master's
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| Page No
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101
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| Abstract
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In this work, our main goal is to synthesize a photocatalyst for efficient hydrogen production. Although there is a huge variety of semiconducting photocatalyst materials for efficient hydrogen production but in most of the cases either because of photocorrosion or photogenerated charges recombination, photocatalyst loses its activity or a noble metal co-catalyst (doping, loading) is required to enhance the stability along with the activity of photocatalytic process. CdxZn1-xS, a solid solution of CdS and ZnS, very famous photocatalyst has been synthesized through the process of thermal sulfurization. Furthermore, for the inhibition of photogenerated charge particles recombination and photocorrosion of photocatalyst, RGO is also decorated on the photocatalyst (RGO-CdxZn1-xS) and electrolyte is supported with S2-,SO32- sacrificial reagent. The process of thermal sulfurization used in this work is very novel of its own kind in which metal oxides are produced in first step and metal sulfides in the other step. By using different ratio of Cd and Zn, ten different samples have been synthesized as Cd0.3Zn0.7S, RGO-Cd0.3Zn0.7S, Cd0.5Zn0.5S, RGO-Cd0.5Zn0.5S, Cd0.7Zn0.3S, RGO-Cd0.7Zn0.3S, Cd0.9Zn0.1S, RGO-Cd0.9Zn0.1S, CdS, and RGO-CdS. For the preparation of photoelectrode, spin coating technique was employed. After optimizing the annealing temperature, number of coating layers, and RGO contents, prepared photoelectrodes are characterized with X-ray diffraction analysis XRD, Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), UV-Vis diffusive reflectance spectroscopy. After characterization, prepared photoanodes were tested photoelectrochemically. Incredible photo-activity along with photostability is very prominent in all tests. However, it is seen that with the increase in Cd-contents, the photo-activity (photocurrent density, hydrogen production rate) and photo-stability of photocatalysts increases remarkably. Out of all the synthesized and prepared samples, RGO-CdS exhibit the highest photocurrent density of 6.5 mAcm-2 and reaches almost 89% of its theoretical value. The applied bias photon-to-current efficiency (ABPE) appears to be 2.67% at 0 Vbias (vs. Pt) which is the highest obtained photocurrent value and yield of RGO-CdS as compared to literature. The rate of hydrogen production for RGO-CdS comes out to be 551.1 μmolsa-1. As a result of this work, we proposed RGO-CdS as an efficient photocatalyst possessing excellent photostability and has a potential for the use in the future researches and applications.
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Inorganic chemistry
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