Probing local photophysical properties in perovskite based light-emitting devices
Miguel Anaya a, Kyle Frohna a, Linsong Cui a, Javad Shamsi a, Sam Stranks a
a Optoelectronics Group, Cavendish Laboratory, University of Cambridge, UK., J.J. Thomson Avenue, Cambridge, United Kingdom
nanoGe Perovskite Conferences
Proceedings of International Conference on Perovskite Thin Film Photovoltaics and Perovskite Photonics and Optoelectronics (NIPHO20)
Sevilla, Spain, 2020 February 23rd - 25th
Organizer: Hernán Míguez
Oral, Miguel Anaya, presentation 048
Publication date: 25th November 2019

Metal-halide perovskites have emerged over the past years as a versatile class of semiconductors for high-performance optoelectronic devices.[1] Despite their unique properties, this family of perovskites has however been observed to display strong instability, especially when electrostimulated, limiting their definitive integration in real-world light-emitting devices.[2,3]

In this talk, we will present a detailed photophysical characterisation of blue-, green- and red-emitting metal halide perovskite films in which different passivation strategies are employed to improve both their optical and electrical properties. We will introduce a new powerful technique with which we can extract the absorptance and photoluminescence quantum efficiency (PLQE) values in the materials at the nanoscale by hyperspectral wide-field imaging. We will then show how our methodology can be extended to characterise operando LEDs and obtain maps at the diffraction limit scale for their External Quantum Efficiency, luminance and luminous efficacy. Our observations allow us to identify the degradation paths of these emerging class of LEDs, revealing microscale heterogeneities that are remarkably suppressed in the passivated samples. Our results open avenues to diagnose the optoelectronic quality of novel semiconductors at the microscale and identify strategies to integrate them in LEDs with spatially maximised performance.

M.A. acknowledges funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 841386. We acknowledge the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (HYPERION, Grant Agreement No. 756962). S.D.S. thanks the Royal Society and Tata Group (UF150033). The authors thank the Engineering and Physical Sciences Research Council (EPSRC) for support. K.F. acknowledges a George and Lilian Schiff Studentship, Winton Studentship, the Engineering and Physical Sciences Research Council (EPSRC) studentship, Cambridge Trust Scholarship, and Robert Gardiner Scholarship.

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