Tuning CH3NH3Pb(I1−xBrx)3 perovskite oxygen stability in thin films and solar cells
- 17 March 2017
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of Materials Chemistry A
- Vol. 5 (20), 9553-9560
- https://doi.org/10.1039/c7ta00058h
Abstract
The rapid development of organic–inorganic lead halide perovskites has resulted in high efficiency photovoltaic devices. However the susceptibility of these devices to degradation under environmental stress has so far hindered commercial development, requiring for example expensive device encapsulation. Herein, we have investigated the stability of CH3NH3Pb(I1−xBrx)3 [x = 0–1] thin films and solar cells under controlled humidity, light, and oxygen conditions. We show that higher bromide ratios increase tolerance to moisture, with x = 1 thin films being stable to 120 h of moisture stress. Under light and dry air, partial bromide (x < 1) substitution does not enhance film stability significantly, with the corresponding solar cells degrading within two hours. In contrast, CH3NH3PbBr3 films show excellent stability, with device stability being limited by the organic interlayer. For these x = 1 films, we show that charge carriers are quenched in the presence of oxygen and form superoxide; however in contrast to perovskites containing iodide, this superoxide does not degrade the crystal. Our observations show that iodide limits the oxygen and light stability of CH3NH3Pb(I1−xBrx)3 perovskites, but that CH3NH3PbBr3 provides an opportunity to develop inherently stable high voltage photovoltaic devices and 4-terminal tandem solar cells.Keywords
Funding Information
- Engineering and Physical Sciences Research Council (EP/M023532/1, EP/K010298/1 and EP/K030671/1)
This publication has 28 references indexed in Scilit:
- Reversible photo-induced trap formation in mixed-halide hybrid perovskites for photovoltaicsChemical Science, 2014
- A Layered Hybrid Perovskite Solar‐Cell Absorber with Enhanced Moisture StabilityAngewandte Chemie-International Edition, 2014
- A Layered Hybrid Perovskite Solar‐Cell Absorber with Enhanced Moisture StabilityAngewandte Chemie, 2014
- Solvent engineering for high-performance inorganic–organic hybrid perovskite solar cellsNature Materials, 2014
- Carbon‐Double‐Bond‐Free Printed Solar Cells from TiO2/CH3NH3PbI3/CuSCN/Au: Structural Control and Photoaging EffectsChemphyschem, 2014
- Sequential deposition as a route to high-performance perovskite-sensitized solar cellsNature, 2013
- Chemical Management for Colorful, Efficient, and Stable Inorganic–Organic Hybrid Nanostructured Solar CellsNano Letters, 2013
- Efficient Hybrid Solar Cells Based on Meso-Superstructured Organometal Halide PerovskitesScience, 2012
- Lead Iodide Perovskite Sensitized All-Solid-State Submicron Thin Film Mesoscopic Solar Cell with Efficiency Exceeding 9%Scientific Reports, 2012
- Organometal Halide Perovskites as Visible-Light Sensitizers for Photovoltaic CellsJournal of the American Chemical Society, 2009