Séminar : Novel Processing Techniques and Materials for High-Performance Flexible Electronics

Jayanta Baral will present his research Thursday 27th November 2014 at 11 am, room 40 building 40 of the CNRS campus in Cronenbourg.

Title : Novel Processing Techniques and Materials for High-Performance Flexible Electronics

Abstract : The vertical phase segregation in a typical polymer/PCBM system leads to a polymer-rich layer at the top of the active layer, limiting electron transport to the cathode, therefore a modest power conversion efficiency (PCE) is observed. We have designed a system which mitigates this unfavorable vertical phase segregation by separating the polymer and PCBM deposition steps while still maintaining good interpenetration of the respective phases. The P3HT component of the active layer are spun first, and by subsequently spin coating PCBM from dichloromethane on the P3HT, an intermixed zone is created with a large interfacial region between the P3HT layer and the PCBM layer. Due to the favorable phase gradient formed using this technique, the devices exhibited a significant enhancement in photocurrent density and PCE. To enhance the PCE even further, the interface between the active layer and the cathode electrode is tuned through the introduction of ultra-thin layers of various materials...