Analysis of Elemental Distribution in CdSe Nanowires upon Cation-Exchange

Research Goal

Colloidally grown CdSe nanowires (NWs) may serve as templates for the synthesis of metallic Ag2Se NWs via cation exchange. A detailed knowledge of the exchange kinetics and the spatial distribution of the silver ions is essential when designing opto-electronic devices. Thus, Ag2xCd1-xSe NWs were investigated after sequential exchange steps using X-ray fluorescence (XRF) at the scanning X-ray microscope P06 at DESY. The preliminary visualization of the elemental distribution rendered promising results: for the first time, we could detect all involved ions.

However, a comprehensive analysis comprising a sophisticated fitting procedure is still lacking. Especially the analysis of the silver dopant introduced during the initial exchange steps requires customized algorithms for a quantitative analysis of the chemical processes at the nanoscale.

Tasks

• Analysis of pre-existing data with respect to the elemental distribution in Ag2xCd1-xSe NWs upon cation exchange
• Comparison of different fitting methods and development/ refinement of a Python-based procedure
• Correlation of the X-ray microscopy data with supplementary data from laboratory-based measurements (SEM, AFM)
• Participation at synchrotron beamtimes
• Scientific presentation of the results

If you are interested in the project, don’t hesitate to write us an email or talk to us after lectures.

Conditions

Begin: Anytime

Program: Physics, CiS, Nanoscience

Where: DESY

Remote-office regulations may apply, according to the current COVID-19 situation

Language: German, English