| Description: | [DCS Seminar (reserved)] Dr. Ratheesh. K. Vijayaraghavan (Eindhoven University of Technology) -- Nanoscale Aspects of Organic Photovoltaic Devices |
| Date: | Wednesday, Nov 05, 2014 |
| Time: | 2 p.m. - 4 p.m. |
| Venue: | 102, Lecture Hall Complex |
| Details: | The presentation will be focused on various nanoscale aspects of organic photovoltaic and monolayer devices. At the outset, factors affecting the photoinduced charge generation at metal−organic monolayer interfaces will be discussed for Donor-Acceptor hemicyanine dyes using their self assembled monolayer and plasmonic devices. For monolayer devices, the quantum yields of short-circuit photocurrent generation in a liquid junction diode were found to correlates with the strength of the donor moiety of the dyes. Modeling of the photocurrent generation using Marcus theory indicates that the net photocurrent results from asymmetry in the electron transfer rates of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) with the electrodes. The quantum efficiency of short-circuit photocurrent generation were found to decreas for the HOMO levels of the hemicyanine going deeper below the Fermi-level of the metal to which it is anchored. The deeper HOMO level provides a larger driving force for back electron transfer from the metal to the photo-oxidized molecule and suppresses current generation in favor of quenching of the excited state. The later part of the presentation will deal with the synthesis of ultrahigh molecular weight Donor-Acceptor low band gap polymers and investigation of the effect of polymer molecular weight on the performance of their photovoltaic devices. The talk will be concluded with the studies on balanced charge carrier mobility and non doped electroluminescent devices described with C3 symmetrical molecule. |
| Calendar: | Seminar Calendar (entered by arun.ds) |