Tez Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Marmara Üniversitesi, Fen Bilimleri Enstitüsü, Kimya Mühendisliği (İngilizce) Anabilim Dalı, Türkiye
Tez Danışmanı: Atıf Koca; Özge Kerkez Kuyumcu
Tezin Onay Tarihi: 2024
Tezin Dili: İngilizce
Desteklendiği Program: Diğer
Özet:
Hydrogen is a promising energy source for addressing environmental issues and photocatalytic hydrogen production from water is a promising renewable energy process. Cadmium sulfide (CdS) is a widely used photocatalyst; however, the photocorrosion problem causing the low stability and fast charge recombination problem causing the low photocatalytic activity are also well-known. To prevent the stability problem, CdxZn1-xS which has tunable optical properties has become forward. MoS2 is used as an additive to semiconductor photocatalysts due to its wide contact interface, inhibition of charge recombination, low cost, high reactivity for H2 evoluation reaction, and enhancement of visible light response. Transition metal carbides such as Mo2C are excellent electrocatalysts for the production of H2; additionally, they serve as good co-catalysts for most photocatalysts. Modified CdXZn1-XS photocatalysts were examined in hydrogen production under solar illumination. In the first part of the study, CdXZn1-XS was prepared using 1,3-diaminopropane (DAP) and then MoS2 added; in the second part of the study Cd0.7Zn0.3S nanorod was prepared using ethylenediamine (EDA)/water and then MoS2 and MoC-Mo2C were added. Catalysts were characterized by XRD, TEM, SEM, UV-Vis DRS, and electrochemical applications. For the first part, a full factor design was carried out via Minitab 19 to investigate the factors affecting the produced hydrogen amount. Cd/Zn ratio, MoS2 content, and photocatalyst loading were studied. Photocatalytic hydrogen production results were analyzed by ANOVA (Analysis of Variance) and it was concluded that for maximum hydrogen production, Cd/Zn ratio should be in the range of 0.5/0.5 and 0.7/0.3; MoS2 content should be in the range of 2-4% and photocatalyst loading should be 10 mg. For the second part, Cd0.7Zn0.3S nanorods were modified with various amounts of MoS2 and MoC-MoC2. N-Cd0.7Zn0.3S/1% MoS2/1.0% MoC-Mo2C catalyst showed the best result with 133.5 mmol H2 g-1 h-1, while the hydrogen production rate of N-Cd0.7Zn0.3S was 37.2 mmol g-1 h-1.