Imperial College London

DrPiersBarnes

Faculty of Natural SciencesDepartment of Physics

Lecturer in Experimental Solid State Physics
 
 
 
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Contact

 

+44 (0)20 7594 7609piers.barnes

 
 
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Location

 

1003Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Belisle:2016:10.1039/C6EE02914K,
author = {Belisle, RA and Nguyen, WH and Bowring, AR and Calado, P and Li, X and McGehee, MD and Barnes, PRF and O'Regan, BC},
doi = {10.1039/C6EE02914K},
journal = {Energy & Environmental Science},
pages = {192--204},
title = {Interpretation of inverted photocurrent transients in organic lead halide perovskite solar cells; proof of the field screening by mobile ions and determination of the space charge layer widths},
url = {http://dx.doi.org/10.1039/C6EE02914K},
volume = {10},
year = {2016}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - In Methyl Ammonium Lead Iodide (MAPI) perovskite solar cells, screening of the built in field by mobile ions has been proposed as part of the cause of the large hysteresis observed in the current/voltage scans in many cells. We show that photocurrent transients measured immediately (e.g. 100 μs) after a voltage step can provide direct evidence that this field screening exists. Just after a step to forward bias, the photocurrent transients are reversed in sign (i.e. inverted), and the magnitude of the inverted transients can be used to find an upper bound on the width of the space charge layers adjacent to the electrodes. This in turn provides a lower bound on the mobile charge concentration, which we find to be 1 x 1017/cm3. Using a new photocurrent transient experiment, we show that the space charge layer thickness remains approximately constant as a function of bias, as expected for mobile ions in a solid electrolyte. We also discuss additional characteristics of the inverted photocurrent transients that imply either an unusually stable deep trapping, or a photo effect on the mobile ion conductivity.
AU - Belisle,RA
AU - Nguyen,WH
AU - Bowring,AR
AU - Calado,P
AU - Li,X
AU - McGehee,MD
AU - Barnes,PRF
AU - O'Regan,BC
DO - 10.1039/C6EE02914K
EP - 204
PY - 2016///
SN - 1754-5706
SP - 192
TI - Interpretation of inverted photocurrent transients in organic lead halide perovskite solar cells; proof of the field screening by mobile ions and determination of the space charge layer widths
T2 - Energy & Environmental Science
UR - http://dx.doi.org/10.1039/C6EE02914K
UR - http://hdl.handle.net/10044/1/50779
VL - 10
ER -