Nb&lt;SUB&gt;2&lt;/SUB&gt;O&lt;SUB&gt;5&lt;/SUB&gt; hole blocking layer for hysteresis-free perovskite solar cells

Fernandes, Silvia L.; Véron, Anna C.; Neto, Nilton F.A.; Nüesch, Frank A.; Dias da Silva, José H.; Zaghete, Maria A.; de O.Graeff, Carlos F.

doi:10.1016/j.matlet.2016.06.018

Nb₂O₅ hole blocking layer for hysteresis-free perovskite solar cells

Fernandes SL, Véron AC, Neto NFA, Nüesch FA, Dias da Silva JH, Zaghete MA & de O.Graeff CF

Citation

Fernandes, S. L., Véron, A. C., Neto, N. F. A., Nüesch, F. A., Dias da Silva, J. H., Zaghete, M. A., & de O.Graeff, C. F. (2016). Nb₂O₅ hole blocking layer for hysteresis-free perovskite solar cells. Materials Letters, 181, 103-107. https://doi.org/10.1016/j.matlet.2016.06.018

Persistent URL https://www.dora.lib4ri.ch/empa/islandora/object/empa:13397

Perovskite solar cells have attracted attention due its high conversion efficiency and low cost. In this work, Nb₂O₅ is used as an alternative compact hole blocking layer in conjunction with mesoporous TiO₂ and CH₃NH₃PbI₃ in perovskite solar cells. The influence of Nb₂O₅ layer thickness was studied and it was found to strongly influence the J-V hysteresis of the cells. Devices constructed with 50 nm Nb₂O₅ have small or undetectable hysteresis, which becomes detectable and increases with increasing Nb₂O₅ layer thickness. For the best device, energy conversion efficiency of up to 12%, short-circuit currents of 17 mA/cm² and fill factors of 74% were found. These parameters are comparable to the best performance of similar devices where the compact layer is TiO₂. In addition, the use of Nb₂O₅ improved the stability of the solar cells under illumination. These improvements are attributed to a better extraction of photogenerated electrons in the perovskite layer.