Recombination and localization

Recombination and localization: Unfolding the pathways behind conductivity losses in Cs₂AgBiBr₆ thin films

Jöbsis, Huygen J. (Universiteit Utrecht)
Caselli, V.M. (TU Delft ChemE/Opto-electronic Materials)
Askes, Sven H.C. (AMOLF)
Garnett, Erik C. (AMOLF)
Savenije, T.J. (TU Delft ChemE/Opto-electronic Materials)
Rabouw, Freddy T. (Universiteit Utrecht)
Hutter, Eline M. (Universiteit Utrecht)

2021

Cs₂AgBiBr₆ (CABB) has been proposed as a promising nontoxic alternative to lead halide perovskites. However, low charge carrier collection efficiencies remain an obstacle for the incorporation of this material in optoelectronic applications. In this work, we study the optoelectronic properties of CABB thin films using steady state and transient absorption and reflectance spectroscopy. We find that optical measurements on such thin films are distorted as a consequence of multiple reflections within the film. Moreover, we discuss the pathways behind conductivity loss in these thin films, using a combination of microsecond transient absorption spectroscopy and time-resolved microwave conductivity measurements. We demonstrate that a combined effect of carrier loss and localization results in the conductivity loss in CABB thin films. Moreover, we find that the charge carrier diffusion length and grain size are of the same order of magnitude. This suggests that the material's surface is an important contributor to charge-carrier loss.

http://resolver.tudelft.nl/uuid:3c6b1180-8bbd-470b-bfa3-6742c7e2b0f2

https://doi.org/10.1063/5.0061899

0003-6951

Applied Physics Letters, 119 (13)

Institutional Repository

journal article

© 2021 Huygen J. Jöbsis, V.M. Caselli, Sven H.C. Askes, Erik C. Garnett, T.J. Savenije, Freddy T. Rabouw, Eline M. Hutter