From UV to Near-Infrared light detection: next generation photodetectors for imaging and biometric applications (15/06/23)

Speaker & Affiliation:

Prof.Nicola Gasparini
Department of Chemistry and Centre for Processable Electronics,
Imperial College London, W120BZ, UK.
n.gasparini@imperial.ac.uk

When ?

15th June, 2023 (Thursday), 4.00 pm (IST)

Venue

KPA Auditorium, Department of Materials Engineering

Abstract:

The current success of organic semiconductor technology is mainly driven by the development of organic light- emitting diodes (OLED), which are now routinely employed in display technologies. In the last decade, however, organic photovoltaics (OPV), leveraging the impressive improvement in device efficiency and stability, have gradually moved from a lab curiosity to a niche market. Their recent success has coincided with the rapid development of effective replacements for the fullerene-based materials that have been prevalent as electron acceptor materials until recently; namely the small molecule nonfullerene acceptors (NFAs). This relatively new class of materials offer a number of opportunities to develop new areas of research. Between those, organic photodetector (OPD), a technology based on organic photodiodes and thus closely related to OPV, is one of the most exciting. Recent efforts in the field of OPD have been focused on extending broadband detection into the near-infrared (NIR) region. The early absorption cut-off of solution processed organic semiconductors presents a challenge in achieving NIR detection, however, careful tuning of their chemical structures can help extend OPD responsivity into the infrared window. Here, we discuss how to design donor:acceptor blends and control charge carrier recombination in organic photodetectors for NIR light-to- current conversion for high efficiency and stable devices.

Short Bio:

Dr. Nicola Gasparini received his B.Sc. and M.Sc, in Chemistry and Organic Chemistry, and Photochemistry and Molecular Materials, respectively, from the University of Bologna, Italy. In 2014 he joined the group of Professor Brabec in the Institute of Materials for Electronics and Energy Technology (i-MEET) at the Friedrich Alexander University Erlangen-Nürnber (FAU) and received his PhD in 2017. In September 2017, he joined the King Abdullah University of Science and Technology (KAUST) as a postdoctoral fellow. In September 2019, he moved to the Department of Chemistry of Imperial College London as an independent researcher holding the Imperial College Research Fellowship. In early 2022, Nicola was appointed Lecturer in Chemistry (assistant professor, tenured) in the Department of Chemistry. He made major scientific contributions regarding the photophysical properties of organic semiconductors, resulting in over 100 publications. His research interests are in organic semiconductors, with particular interests in charge transport and recombination processes in organic solar cells and photodetectors.