INSPIRE-Grant Report Rishi Ramdas Shivhare
In September 2018, I was offered the INSPIRE grant which gave me the opportunity to work in Professor Natalie Banerji’s lab at the University of Bern in Switzerland. Professor Banerji’s lab specializes in ultrafast spectroscopy of organic semiconductors and is located in the Department of Chemistry and Biochemistry.
As a graduate student at cfaed, I worked on physics and material science aspect of organic solar cells (OSC’s). OSC’s, especially the bulk-heterojunction (BHJ) variants are inherently complex and the charge generation in these cells involves an interplay of many physical processes ranging over nine orders of magnitude in time dynamically. At professor Banerji’s lab, my aim was to use transient absorption spectroscopy (TAS) to study charge transfer dynamics in near-zero driving force bulk-heterojunction blends. Additionally, we used a novel technique known as electromodulated differential absorption (EDA) spectroscopy which provided us with the information about early-time (< 1 ns) charge carrier transport and the mobility dispersion in the devices.
Results obtained in the two months stay at Prof. Banerji’s lab were pivotal for my thesis and provided me with key results and convincing explanations for the findings obtained through other experiments. In the process, I learnt a lot about ultrafast pump-probe spectroscopy and the subsequent data analysis procedure. At the lab, the support from the lab members was incredible and I enjoyed my stay a lot.
Additionally, being in Switzerland, I was surrounded by striking natural beauty all around. The panorama of the alpine peaks from the main university building was simply breathtaking. During my stay I also managed to visit Interlaken and the city of Lucerne, which were again quite stunning.