|
|||||
|
|
Boosting the Efficiency of Perovskite Solar Cells with CsBr‐Modified Mesoporous TiO2 Beads as Electron‐Selective Contact |
|
| Authors: | Ji‐Youn Seo Ryusuke Uchida Hui‐Seon Kim Yasemin Saygili Jingshan Luo Chris Moore Julie Kerrod Anthony Wagstaff Mike Eklund Robert McIntyre Norman Pellet Shaik M. Zakeeruddin Anders Hagfeldt Michael Grätzel |
| Affiliation: | 1. Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, école Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland;2. Advanced Research division, Materials and Devices Research Laboratory, Panasonic Corporation, Kadoma City, Osaka, Japan;3. Laboratory of Photomolecular Science, Institute of Chemical Sciences and Engineering, école Polytechnique Fédérale de Lausanne, Lausanne, Switzerland;4. Dyesol UK, UMIC, Incubator Building, University of Manchester, UK;5. Cristal Technology and Innovation Group, Stallingborough, Grimsby, UK |
| Abstract: | Rapid extraction of photogenerated charge carriers is essential to achieve high efficiencies with perovskite solar cells (PSCs). Here, a new mesoscopic architecture as electron‐selective contact for PSCs featuring 40 nm sized TiO2 beads endowed with mesopores of a few nanometer diameters is introduced. The bimodal pore distribution inherent to these films produces a very large contact area of 200 m2 g?1 whose access by the perovskite light absorber is facilitated by the interstitial voids between the particles. Modification of the TiO2 surface by CsBr further strengthens its interaction with the perovskite. As a result, photogenerated electrons are extracted rapidly producing a very high fill factor of close to 80% a VOC of 1.14 V and a PCE up to 21% with negligible hysteresis. |
| Keywords: | cesium doping hysteresis mesoporous TiO2 passivation perovskite solar cells photovoltaics |