Abstract
The remarkable properties of metal halide perovskites arising from their impressive charge carrier diffusion lengths have led to rapid advances in solution-processed optoelectronics. Unfortunately, diffusion lengths reported in perovskite single crystals have ranged widely – from 3 μm to 3 mm – for ostensibly similar materials. Here we report a contactless method to measure the carrier mobility and further extract the diffusion length: our approach avoids both the effects of contact resistance and those of high electric field. We vary the density of quenchers – epitaxially included within perovskite single crystals – and report the dependence of excited state lifetime in the perovskite on inter-quencher spacing. Our results are repeatable and self-consistent (i.e. they agree on diffusion length for many different quencher concentrations) to within ± 6%. Using this method, we obtain a diffusion length in metal-halide perovskites of 2.6 μm ± 0.1 μm.
| Original language | English (US) |
|---|---|
| Article number | 1591 |
| Journal | Nature communications |
| Volume | 10 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 1 2019 |
Funding
This publication is based in part on work supported by the US Department of the Navy, Office of Naval Research (Grant Award No.: N00014-17-1-2524), by the Ontario Research Fund Research Excellence Program, and by the Natural Sciences and Engineering Research Council (NSERC) of Canada. The authors thank L. Levina for the assistance in CQDs synthesis, A. Lough, Y. Gao for single crystal XRD, P. Brodersen for TOF-SIMS and E. Palmiano, R. Wolowiec, and D. Kopilovic for their help during the course of study. X.G. thanks Mitacs for a Globalink Graduate Fellowship Award. M.I.S. acknowledges the support of the Banting Postdoctoral Fellowship Program, administered by the Government of Canada.
ASJC Scopus subject areas
- General Chemistry
- General Biochemistry, Genetics and Molecular Biology
- General Physics and Astronomy