Bismuth-Iodide-Assisted Crystallization and Stability in Cs-Containing and Cs-Free Hybrid Perovskites
Makaleler > Tam Makale · 2025
Yazarlar: Adem MUTLU, Ceylan ZAFER
Crystal Growth & Design, SCI Expanded İndekslerine Giren Dergi, Uluslararası, Wos, 2025, cilt 25, ss 9448-9460
Özet
This study investigates the structural, morphological, and chemical effects of bismuth(III) iodide (BiI 3 ) incorporation on perovskite films containing Cs +, FA +, and MA + cations. Cs + -containing (CsFAMA) and Cs + -free (FAMA) structures were comparatively evaluated at 1, 3, and 5 wt % BiI 3 . X-ray diffraction (XRD) revealed that low doping levels enhanced phase purity, while higher concentrations induced morphological degradation, as confirmed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The incorporation of BiI 3 was confirmed by energy-dispersive X-ray spectroscopy (EDX), while X-ray photoelectron spectroscopy (XPS) analyses further verified the chemical states of Bi and Pb. In the FAMA structure, the Bi 0 signals indicated reduction tendencies, whereas the presence of Bi 3+ suggested partial incorporation through doping. BiI 3 suppressed the Pb 0 states, improving oxidative stability and structural integrity. XRD analysis of the ∼2θ 12.2° peak showed that without BiI 3, intermediate phases formed at low temperatures, whereas BiI 3 altered crystallization kinetics, stabilizing this phase at higher temperatures. Cs + addition further suppressed PbI 2 and nonphotoactive δ-FAPbI 3 phases, enhancing thermal stability. Two-week aging tests revealed that CsFAMA films with BiI 3 maintained their crystal phase longer and exhibited reduced PbI 2 formation. These results demonstrate that BiI 3 provides both chemical and structural modification, with Cs + significantly influencing its impact. This work highlights the synergistic role of Cs + and Bi in stabilizing perovskites, offering new insights for durable perovskite solar cells.