Carrier Dynamics in Upconverting Thin Film Perovskite/Rubrene Bilayers Studied by Combined Surface Photovoltage and Photoluminescence
Karunanantharajah Prashanthan a, Igal Levine a, Emilio Gutierrez-Partida b, Artem Musiienko a, Hannes Hempel a, Klaus Lips a, Thomas Unold a, Martin Stolterfoht b, Thomas Dittrich a, Rowan W. MacQueen a
a Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin, Germany
b Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24–25, D-14476 Potsdam-Golm, Germany
International Conference on Hybrid and Organic Photovoltaics
Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV22)
València, Spain, 2022 May 19th - 25th
Organizers: Pablo Docampo, Eva Unger and Elizabeth Gibson
Oral, Karunanantharajah Prashanthan, presentation 063
Publication date: 20th April 2022

We studied the excited state dynamics of a photon upconversion system consisting of lead halide perovskite thin film layered with rubrene annihilator. This system exhibits triplet-triplet annihilation upconversion from the near-infrared to the visible spectrum, wherein the perovskite film acts as a triplet sensitizer, while the rubrene layer functions as the annihilator and emitter. A key feature of this style of upconverter, which removes the conventional excitonic triplet sensitizer[1] and replaces it with the interface of a bulk semiconductor film, is the conversion of electron-hole pairs in the perovskite into strongly-bound excitons within the organic annihilator film. The process represents an emerging application of lead halide perovskites beyond the photovoltaics space, and is of interest both as a photonics application, and as a fundamental investigation into energy transduction processes at hybrid semiconductor interfaces[2].


Our study aims to generate new insights into these perovskite upconverter systems using a combination of transient surface photovoltage and photoluminescence methods [3, 4]. Transient surface photovoltage measures the transient electrical polarization across a semiconductor film stack resulting from carrier diffusion, trapping, dissociation of excitons, and recombination following excitation by a short laser pulse. As such, it offers insight into the net charge distribution throughout the sample as well as the rates of various carrier transfer and recombination processes.


We measured intensity-dependent SPV transients along with photoluminescence transients under similar excitation conditions, allowing us to make a like-for-like comparison of the internal processes telegraphed by both measurements. Additionally, through modifying the perovskite synthesis, we were able to influence the charge distribution in the perovskite film and observe the corresponding impact on the exciton generation process.

K.P. acknowledges the Deutscher Akademischer Austauschdienst (DAAD) for funding via the Research Grants - Doctoral Programmes in Germany, 2018/19 (57381412). R.W.M. acknowledges the Helmholtz Association, Germany, for funding within the Helmholtz Excellence Network SOLARMATH, a strategic collaboration of the DFG Excellence Cluster MATH+ and Helmholtz-Zentrum Berlin (Grant No. ExNet-0042-Phase-2-3).

We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info