Precursor Engineering of Lead Acetate-Based Precursors for High-Open-Circuit Voltage Wide-Bandgap Perovskite Solar Cells

Abstract

Wide-bandgap (WBG) perovskites have great potential for inclusion in efficient tandem solar cells, but large open-circuit voltage losses have limited device performance to date. Here, we show that a high-quality WBG perovskite, FA0.83Cs0.17Pb­(I0.8Br0.2)3, with enlarged grain sizes and improved crystallinity can be achieved by incorporating lead chloride (PbCl2) into a lead acetate (PbAc2)-based precursor. The improved film quality resulted in the suppression of nonradiative recombination and a reduction in defect density. Efficient WBG perovskite solar cells (1.66 eV) with an efficiency of 19.3% and a high V oc of 1.22 V were fabricated using a facile one-step spin-coating method without the need for an antisolvent. Notably, the unencapsulated devices retained 90% of their initial power conversion efficiency after storage in a dry box (10% humidity) for 800 h.

Defect passivation engineering of wide-bandgap perovskites for high-performance solar cells

“…Both phase segregation and defects can contribute to instability in WBG perovskites. 43 On the one hand, the migration of halide anions, facilitated by structural defects within the perovskite lattice, exerts a significant influence on phase segregation. Investigations have indicated that phase segregation predominantly manifests at grain boundaries, known for their heightened defect density compared to the grain interior.…”

Heterogeneity of Light-Induced Open-Circuit Voltage Loss in Perovskite/Si Tandem Solar Cells

“…Figure S4 presents the time evolution of PL spectra of a perovskite film in a nitrogen environment. The segregation of iodide ions stopped after 45 min of light exposure, implying saturation of iodide ions at the grain boundaries . The PL spectra of the target sample remain nearly unchanged, even after extended illumination.…”

Ecofriendly Solution Processing of Perovskite Solar Cells Using Water

“…Various lead halide (PbCl 2 ) and nonhalide lead precursors including Pb­(OAc) 2 (OAc = CH 3 CH 2 COO – ), Pb­(NO 3 ) 2 , Pb­(acac) 2 (acac = (CH 3 COCHCOCH 3 ) − ), and PbCO 3 have been explored as potential precursors for perovskite solar cell preparation using conventional organic solvent methods. However, the performance of the resulting PSCs has been hindered by challenges related to inadequate phase and morphological control. − …”