Prof. Dr. Somnath Bhattacharyya 

The search for new materials – electrocatalysts - that should allow us to access cheap and

reliable energy and to enable decarbonization of our economy requires advanced chemical

techniques that allow investigating chemical processes with high magnification. In this project

we aim to provide a guide on bringing a chemical microscopy technique – tip-enhanced Raman

spectroscopy (TERS) – to work in real world environments. The biggest challenge so far for this

advanced tool was related to stability of a scanning tip, which is both difficult to produce and is

also rather unstable in liquids. To overcome this issue we are employing a novel approach of

trapping a small nanoscale particle at a tip of a mobile nanopore, an approach that should

replace a traditional way of making these probes. Modern chemistry is very flexible to produce

such particles in large numbers, they are stable and provide all necessary optical and chemical

properties. The major difficulty is to catch this particle and reliably attach it to a nanoscale tip.

To “fish” these particles we will employ electroosmosis, a peculiar phenomenon that occurs

due to the movement of ions dissolved in liquid, which causes a fluid flow. In this project we will

develop a theoretical model that describes this phenomenon in high detail. Based on numerical

simulations of the set of partial differential equations governing these phenomena, we will

determine the parameters for manipulating the flow and trapping the nanoparticles.