Efficient and Stable MAPbI<sub>3</sub>-Based Perovskite Solar Cells Using Polyvinylcarbazole Passivation
Lyubov A. Frolova, Aivaz I. Davlethanov, Nadezhda N. Dremova, Ivan S. Zhidkov, Azat F. Akbulatov, E.Z. Kurmaev, С. М. Алдошин, Keith J. Stevenson, Pavel A. Troshin
Abstract
Hybrid perovskite solar cells attract a great deal of attention due to the feasibility of their low-cost production and their demonstration of impressive power conversion efficiencies (PCEs) exceeding 25%. However, the insufficient intrinsic stability of lead halides under light soaking and thermal stress impedes practical implementation of this technology. Herein, we show that the photothermal aging of a widely used perovskite light absorber such as MAPbI 3 can be suppressed significantly by using polyvinylcarbazole (PVC) as a stabilizing agent. By applying a few complementary methods, we reveal that the PVC additive leads to passivation of defects in the absorber material. Introducing an optimal content of PVC into MAPbI 3 delivers a PCE of 18.7% in combination with a significantly improved solar cell operational lifetime: devices retained ∼70% of the initial efficiency after light soaking for 1500 h, whereas the control samples without PVC degraded almost completely under the same conditions.