Research Seminar of Prof. Frank Nüesch fromSwiss federal Institute of Technology in Lausanne (EPFL)

Lecture Time: 15:00 on 6th September, 2017

Lecture Room: C501 of Science and Innovation Building

Lecture Title:Cyanine Dyes for Optoelectronic Applications

Frank Nüesch

Head of Laboratory at the Swiss Federal Laboratories for Materials Science and Technology (EMPA) in Dübendorf

Honorary Professor at Swiss federal Institute of Technology in Lausanne (EPFL)

Abstract

Cyanines are strongly absorbing and highly luminescent dyes consisting of a cationic chromophore and an anionic counterion. Today they are well known as fluorescent markers in biology and biochemistry and numerous works consist of covalently linking the dyes to biomolecules such as proteins or sugars. Recently these dyes have been used in optoelectronic applications, which brings them back more closely to their original use as sensitizers in silver-halide photography. Applied as thin films, they behave as organic semiconductors and can transport charges and excited states, produce photocurrent or emit light. The fact that cyanine dyes are salts offers the possibility for thin films to be poled and to tune intrinsic semiconducting properties such as charge carrier mobility or solubility. This presentation gives an overview of our recent developments in the field of thin film cyanine devices highlighting visible and NIR sensitive solar cells and photodiodes as well as light emitting electrochemical cells. The fact that these organic semiconductors can be deposited from solution opens up applications in the raising field of printed electronics.

Selected publications:

1) H. Zhang et al., Solar Energy Mater Solar Cells 2013, 118, 157-164.

2) H. Zhang et al., Scientific Reports 2015, 5, 9439.

3) M. Makha et al.,Science and Technology of Advanced Materials, 2017, 18.68-75.

4) S. Jenatsch et al, ACS Appl. Mater. Interfaces 2016, 8, 6554?6562.

5) S. Jenatsch et al., Organic Electronics 48 (2017) 77-84.

Biography

Frank Nüesch, Head of Laboratory at the Swiss Federal Laboratories for Materials Science and Technology (EMPA) in Dübendorf, Honorary Professor at Swiss federal Institute of Technology in Lausanne (EPFL), obtained a physics diploma at ETH Zurich and doctoral degree at EFPL under Professor Michael Gr?tzel's supervision on the subject of the photochemical properties of solar cells sensitized by colorant. In Prof. Frank Nüesch’s Group, the main research interest is devoted to the research and development of novel organic materials and polymers with unique functional properties, designed for future technological applications, including chemical synthesis, chemical and physical characterization methods as well as thin film device fabrication.