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Revealing Charge Carrier Mobility and Defect Densities in Metal Halide Perovskites via Space-Charge-Limited Current Measurements

[Image: see text] Space-charge-limited current (SCLC) measurements have been widely used to study the charge carrier mobility and trap density in semiconductors. However, their applicability to metal halide perovskites is not straightforward, due to the mixed ionic and electronic nature of these mat...

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Detalles Bibliográficos
Autores principales: Le Corre, Vincent M., Duijnstee, Elisabeth A., El Tambouli, Omar, Ball, James M., Snaith, Henry J., Lim, Jongchul, Koster, L. Jan Anton
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2021
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8043077/
https://www.ncbi.nlm.nih.gov/pubmed/33869770
http://dx.doi.org/10.1021/acsenergylett.0c02599
Descripción
Sumario:[Image: see text] Space-charge-limited current (SCLC) measurements have been widely used to study the charge carrier mobility and trap density in semiconductors. However, their applicability to metal halide perovskites is not straightforward, due to the mixed ionic and electronic nature of these materials. Here, we discuss the pitfalls of SCLC for perovskite semiconductors, and especially the effect of mobile ions. We show, using drift-diffusion (DD) simulations, that the ions strongly affect the measurement and that the usual analysis and interpretation of SCLC need to be refined. We highlight that the trap density and mobility cannot be directly quantified using classical methods. We discuss the advantages of pulsed SCLC for obtaining reliable data with minimal influence of the ionic motion. We then show that fitting the pulsed SCLC with DD modeling is a reliable method for extracting mobility, trap, and ion densities simultaneously. As a proof of concept, we obtain a trap density of 1.3 × 10(13) cm(–3), an ion density of 1.1 × 10(13) cm(–3), and a mobility of 13 cm(2) V(–1) s(–1) for a MAPbBr(3) single crystal.