The device physics of metal halide perovskite interfaces, part 2: equivalent circuit model

Davide Moia^a^,^b, Ilario Gelmetti^c^,^d, Phil Calado^a, William Fisher^a, Michael Stringer^e, Onkar Game^e, Yinghong Hu^f, Pablo Docampo^f^,^g, David Lidzey^e, Emilio Palomares^c^,^h, Joachim Maier^b, Jenny Nelson^a, Piers Barnes^a

^aDepartment of Physics, Imperial College London, United Kingdom

^bMax Planck Institute for Solid State Research, Stuttgart, Heisenbergstraße, 1, Stuttgart, Germany

^cInstitute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Avinguda dels Països Catalans, 16, Tarragona, Spain

^dDepartament d’Enginyeria Electrònica, Elèctrica i Automàtica, Universitat Rovira i Virgili, Avinguda dels Països Catalans, 26, Tarragona, Spain

^eDepartment of Physics and Astronomy, University of Sheffield, UK, Hounsfield Road, United Kingdom

^fUniversity of Munich (LMU), Department of Chemistry and Center for Nanoscience (CeNS), 81377 Múnich, Alemania, Múnich, Germany

^gPhysics Department, School of Electrical and Electronic Engineering, Newcastle University, United Kingdom, Merz Court, Newcastle upon Tyne NE1 7RU, Reino Unido, United Kingdom

^hInstitució Catalana de Recerca i Estudis Avançats (ICREA), Spain, Passeig Lluis Companys 23, Barcelona, Spain

International Conference on Hybrid and Organic Photovoltaics
Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV19)

Roma, Italy, 2020 May 12th - 14th

Organizers: Prashant Kamat, Filippo De Angelis and Aldo Di Carlo

Poster, Davide Moia, 135
Publication date: 6th February 2020

Our recent drift-diffusion simulations indicate that the electrostatic potential arising from mobile ion redistribution controls electronic charge transfer processes such as recombination in mixed conducting lead halide perovskite devices and can give rise to apparent capacitive behavior.[1] The capacitive features of a mixed conductor are traditionally described within equivalent circuit models by a chemical capacitance, which accounts for bulk polarization effects.[2,3] and scales with the thickness of the device, complemented by an interfacial capacitance, related to electronic and ionic accumulation at the interfaces with the contacts. Since the effect described is not simply associated with an accumulation or depletion of charges in the active layer, it cannot be adequately described with a conventional capacitor. We identify the bipolar transistor as a most appropriate circuit element to reproduce analytically the observation of ionically-gated electron transfer at interfaces and include it into an equivalent circuit model that accounts for and couples ionic and electronic carrier dynamics.[1] We propose that the huge capacitive and/or inductive behavior[4] observed for thin film perovskite solar cells is best described by electronic currents that are in fact an amplified version of the ionic current flowing in the bulk of the active layer. The resulting model yields good fits to the experimental impedance spectra as a function of applied voltage bias and light intensity, and can reproduce large perturbation transient measurements such as hysteretic current-voltage characteristics.[5] It also enables to evaluate parameters such as the ionic conductivity of the hybrid perovskite, the observed ideality factor of the device and the properties of the space charge within the active layer and in the contact regions. The limits under which the present model coincides with the traditional picture are discussed.

References:

[1] Moia, D.; Gelmetti, I.; Calado, P.; Fisher, W.; Stringer, M.; Game, O.; Hu, Y.; Docampo, P.; Lidzey, D.; Palomares, E.; et al. Ionic-to-Electronic Current Amplification in Hybrid Perovskite Solar Cells. arXiv:1805.06446v2 [physics.app-ph] 2018.

[2] Senocrate, A.; Moudrakovski, I.; Kim, G. Y.; Yang, T.-Y.; Gregori, G.; Grätzel, M.; Maier, J. The Nature of Ion Conduction in Methylammonium Lead Iodide: A Multimethod Approach. Angew. Chem. Int. Ed. Engl. 2017, 56 (27), 7755–7759.

[3] Jamnik, J.; Maier, J. Generalised Equivalent Circuits for Mass and Charge Transport: Chemical Cpacitances and Its Implications. Phys. Chem. Chem. Phys. 2001, 3 (9), 1668–1678

[4] Almora, O.; Cho, K. T.; Aghazada, S.; Zimmermann, I.; Matt, G. J.; Brabec, C. J.; Nazeeruddin, M. K.; Garcia-Belmonte, G. Discerning Recombination Mechanisms and Ideality Factors through Impedance Analysis of High-Efficiency Perovskite Solar Cells. Nano Energy 2018, 48 (February), 63–72.

[5] Snaith, H. J.; Abate, A.; Ball, J. M.; Eperon, G. E.; Leijtens, T.; Noel, N.; Stranks, S. D.; Wang, J. T. W.; Wojciechowski, K.; Zhang, W. Anomalous Hysteresis in Perovskite Solar Cells. J. Phys. Chem. Lett. 2014, 5 (9), 1511–1515

Acknowledgements:

We thank the EPSRC for funding this work (EP/J002305/1, EP/M025020/1, EP/M014797/1, EP/L016702/1, EP/R020590/1). I.G. and E.P. would like to thank the MINECO for the CTQ2016-80042-R project. E.P. also acknowledges AGAUR for the SGR project 2014 SGR 763 and ICREA for financial support.

nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.

MATSUS

Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.

International Conference on Hybrid and Organic Photovoltaics

International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.

Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics

The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.

International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics

The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.