In order to measure catalytic activity of a single isolated nanoparticle one must seal it inside a micron-sized volume with the reaction gas. There is currently a large research effort working towards this goal at DTU Physics.
We have developed MEMS devices (chips) with such tiny cavities which can be sealed using a layer of graphene – and which are TEM transparent.
You will use graphene or hBN to seal cavities on these chips in various gasses and gas mixtures and measure how the gas leaks (or or reacts) over time – and as a function of temperature. In order to measure this you will use at least one of the following three methods:
- AFM – observing the time-evolution of the pressure induced static deflection of the graphene sealing membranes.
- TEM – measuring EELS spectra of the captive gas and observing the signal over time.
- Laser interferometry – the graphene sealing membranes can be excited to vibrate (like a drum head) and the frequency changes with gas pressure. The vibration can be detected as a phase shift of a laser beam reflecting off the membrane.
The project will be part of the ongoing VISION research initiative at DTU Physics.
Forudsætninger
Main prerequisite: Ambition to master several experimental techniques and push the state of the art. Course 10304 is an advantage.
