Semester Projects
(can be adapted to Bachelor or Master level)
Prototyping a customized heating gas cell for real time TEM observations of fuel cell catalysts
AvailablePerformance of Pt/C nanocatalysts for fuel cell cathodes have been shown to dramatically improve after an annealing step in ambient atmosphere. The mechanism of this improvement however remains poorly understood, and real time analysis of the chemical and structural modifications at the nanoscale would be beneficial. In situ heating TEM is a powerful technique to access such real time information but maintaining environmental conditions throughout the experiment is challenging. The aim of this project is to prototype a novel gas-cell enclosure compatible with a dedicated specimen holder for heating in the TEM, so that the sample can be kept in air and isolated from the column vacuum. The student will experiment with different configurations involving MEMS-based chips and evaluate their merits under operational conditions.
Contact: Mr. Robin GirodMEMs-based chips for in situ TEM applications
ReservedThe aim of this project is to fabricate MEMS-based chips for in situ TEM applications such as biasing, heating, and electrochemistry. The student will be introduced to MEMS technologies such as photolithography, etching process, thin film deposition, etc. The process of the chip fabrication will take place in the cleanroom at the Center of Micronanotechnology (CMi). The student is expected to understand the fundamentals of MEMS technologies and obtain hands-on experience of semiconductor processing. The MEMS processing skills obtained after this project are highly transferable especially in semiconductor industries. Previous hands-on experience in cleanroom is preferred for this project.
Contact: Mr. Jan Vavra and Mr. Morgan BinggeliTesting of passivation layers in microfabricated MEMS chips for electrochemical applications
ReservedThe aim of this project is to implement a new polymeric passivation layer on MEMS-based chips used for electrochemical in situ TEM applications. The student will have to define and optimize a process to fabricate this passivation layer and will test its efficiency. The student will be introduced to MEMS technologies such as photolithography, thin film deposition, etc. and to the basics of electrochemistry phenomena in a TEM liquid cell. The process of the passivation layer fabrication will take place in the cleanroom at the Center of Micronanotechnology (CMi). The student is expected to understand the fundamentals of MEMS technologies and obtain hands-on experience in semiconductor processing. Previous hands-on experience in cleanroom and/or electrochemistry is preferred for this project.
Contact: Mr. Morgan BinggeliSimulations of gas flow channels in ESEM for proton exchange membrane fuel cells
ReservedEnvironmental SEM can be used to observe unique phenomena at the mesoscale, such as liquid water formation in proton exchange membrane fuel cells. The experiment consists of customising a stage that allows the reactants to flow towards the catalyst layer through the porous media of the fuel cell in the ESEM chamber. The goal of this project is to predict the reactants flow towards the catalyst under different gas inlet geometries using COMSOL software, and discuss what modifications could optimize the stage. Vapor condensation on the stage will also be investigated this way. The student will evaluate the validity of the model in the ESEM and in mesoporous media.
Contact: Mr. Michele Bozzetti