Performance measurement and electrode design for application of photo electrochemical hydrogen production

Electrolysis of water by using solar energy via photo electrochemical methods and production of hydrogen gas are studied by science authority, increasing day by day. In this thesis, all studies have same goal with alternative approaches. Hydrogen gas cannot stand in nature by itself. Because of that, it must be produced as energy carrier and called secondary energy source. Traditional hydrogen gas production methods are steam reforming, coal gasification, etc. But all these methods are not preferred because of main constituent, fossil fuel, harming and polluting environment. Photo electrochemical (PEC) solar cells are nature friendly because they are completely reversible and have photoactive electrodes submerged under electrolyte liquid to produce electron-hole pair from water molecules decomposed oxygen and hydrogen. Decomposed oxygen and hydrogen gases are accumulated and stored in different medium for different usage. In this thesis, three different photo-anode configurations and two different electrolyte solutions were studied to use in photo electrochemical systems. Indium sulfide (In2S3) photo-anodes were produced via spray pyrolysis method with different coating thickness and tested under 0.5M Potassium Sulfate (K2SO4) solution. Zinc Oxide nanostructure films produced via chemical bath deposition (CBD) method were coated with Indium Sulfide to increase photo sensibility and tested under 0.25M Na2S + 0.35M Na2SO3 Sodium Sulfide solution. Properties of absorption of solar energy, electrical conductivity, stability, etc. are affected by Indium Sulfide coating thickness. The other one, pH of the electrolyte solution, directly affects the performance of photo electrochemical system. The last one, Indium Sulfide coating on Zinc Oxide increases the photocurrent density affecting photo electrochemical performance.