Upscaling of a monolithic, photovoltaic-assisted water photoelectrolysis device in alkaline media.

The goal of this thesis is to experimentally study the performance and the characteristics of an up-scaled Photovoltaic-assisted electrochemical cell. Specifically, an amorphous silicon PV was sandwiched between an anode, with a double perovskite cobaltite as a catalyst, and an electrodeposited Ni-Mo on a titanium foil cathode. Firstly, the device’s design was prepared and then built in the laboratory. Then, the whole chassis was assembled, with the anion exchange membranes, the O-rings, and the PV-E cell, along with the stainless steel skeleton where eight screws were placed to pressurize the device and better isolate it from the alkaline solution (KOH) where it was placed in. The bigger box was then connected to a reservoir to recycle the electrolyte and to collect both hydrogen and oxygen through a peristaltic pump. Successively, the illuminated response was estimated through a solar simulator, with the water displacement method as a tool to evaluate the volumetric production rate of Hydrogen gas. Unfortunately, the low rate of the produced gasses and the overall complexity of the setup hindered the possibility of collecting some useful data. Nevertheless, the PV-E cell is completely functioning, and the formation of bubbles that can be seen in the quartz window of the device, due to the water-splitting process occurring at the electrode’s surface, proves the goodness of the up-scaled cell. However, from a future work perspective, several adjustments are needed to consider this project as a functioning reactor. Both engineering and chemical issues need to be solved to allow the measurement of the produced gases.