Semester Projects (can be adapted to Bachelor or Master level)

 

Synthesis and characterisation of BZT ceramics

Available

The lead-free BaTiO3(1-x)-BaZrO3(x) (BZT) solid solution offers accessibility to various ferroelectric and structural phases. Small variations in the BaZrO3 component results in orthorhombic and rhombohedral phases, which in pure BaTiO3 are only accessible by cooling. On the other hand, greater amounts of BaZrO3 forces the material to become relaxor-ferroelectric and to accommodate cubic average structure. The student will perform solid state synthesis of BZT ceramics with various contents of BaZrO3 additive. To check the quality of the ceramics and the crystalline structure of them, x-ray diffractometry (XRD) will be employed. To assess grain structure (size of the grains, porosity, possible unwanted inclusions), scanning electron microscopy (SEM) will be used.

Contact: Mr. Reinis Ignatans


Synthesis of Co-based metal oxides catalysts for oxygen evolution reaction

Available

Co-based metal oxides have been demonstrated catalytic properties for oxygen evolution reaction in alkaline media. The aim is to prepare Co-based metal oxide powders using methods such as co precipitation, solid state, combustion methods, etc. The student is expected to select suitable methods to synthesize the powders. Upon successful synthesis, the student will characterize the powders to understand the properties such as phases, elemental composition, and grain size using X-ray diffraction and electron microscopy techniques.

Contact: Mr. Tzu-Hsien Shen


MEMs-based chips for in situ TEM applications

Available

The aim of this project is to fabricate MEMS-based chip 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 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. Previous hands-on experience in cleanroom is preferred for this project.

Contact: Mr. Tzu-Hsien Shen


Training of a model for content-aware restoration of electron microscopy images

Available

Developments in neural networks and deep learning methods have led to a variety of applications for image treatment and analysis. Electron microscopy of sensitive materials, such as polymers, could benefit from new tools for denoising and image restoration when imaging at low electron dose is required to avoid material degradation. This project aims at making use of the CSBdeep toolbox to define and train a neural network for content aware image restoration of TEM pictures of fuel cell electrodes. Upon successful training, the model will be used in combination with the corresponding FIJI plugin to assess its efficiency against competitive denoising methods. Basic knowledge in programming and python language is preferred.

Contact: Mr. Robin Girod


Enhance epoxy resins structural properties for embedding application

Available

Epoxy resins are a class of reactive polymers containing epoxide groups, they have been widely used for coating and adhesives applications, as well as in electronics industry. Thanks to their flexible chemistry and their curing capability, epoxy resins have been used in research as protective or embedding media for porous samples. In this project the student will investigate the chemical modification strategies of epoxy resins, and try to develop an epoxy resin with enhanced thermal stability and electron microscope Z-contrast by incorporation of transition metal ions. The project includes formation on the surface cleaning techniques to characterize the resins stability.

Contact: Mr. Michele Bozzetti


Design and precision 3D printing of custom liquid cell enclosures

Available

To better understand processes within a thin liquid layer inside a MEMS device for closed cell environmental electron microscopy, it is beneficial to correlate the TEM data with other analytical techniques such as optical microscopy or synchrotron x-ray absorption and fluorescence methods. However, each method has specific requirements in terms of sample mounting and positioning. Goal of this project is to design custom enclosures for these devices in Catia or Solidworks. The enclosures concentrate liquid channels and electrical contacts to an area of several mm2 and make a reliable interface to the MEMS device. Prototypes will be precision 3D printed and their function evaluated.

Contact: Mr. Jan Vavra


Flow profile analysis

Available

Flow profiles in a thin liquid layer inside an in-situ electrochemical cell for TEM will be investigated with the use of particle imaging velocimetry. Goal of this project is to analyze time series images of a tracer fluorescent nanoparticle and enable statistical processing of these variables, which would help understand the complex interplay of externally driven and electroosmotic flow in sub 200 nm water layers. The student will be introduced to particle imaging velocimetry and is expected to write a script using a programming language of his/her choice. Basic programming skills are required.

Contact: Mr. Jan Vavra


ALD coating of nanoporous fuel cell electrodes

Available

Characterization of proton exchange membrane fuel cell (PEMFC) electrodes is important to understand the relationships between morphology at the nanoscale and performance. Transmission Electron Microscopy (TEM) appears as a tool of choice, owing to its high spatial resolution, but can result in structural degradation and radiolysis damages because of the high energy electron beam. This project aims at exploring a way to mitigate such degradation by applying a conformal oxide coating within the porous structure of PEMFC electrode using atomic layer deposition (ALD) in order to encase the primary nano-aggregates and avoid mass loss during imaging. A recipe for low temperature deposition of Al2O3 will be developed and tested at EPFL center for microfabrication (CMi), and applied to PEMFC electrodes. TEM samples will then be prepared by ultramicrotomy at the interdisciplinary center for electron microscopy (CIME) for assessing the efficiency of the method in the TEM.

Contact: Mr. Robin Girod