Defect Passivation through (α-Methylguanido)acetic Acid in Perovskite Solar Cell for High Operational Stability

Abstract

Defect passivation has become essential in improving efficiency and stability in perovskite solar cells. Here, we report the use of (α-methylguanido)acetic acid, also known as creatine, as a passivation molecule. It is employed both as an additive and as a surface passivation layer of perovskite thin films, given its multiple functional groups, which could address different defect sites, and its size, which could inherently affect the material structure. We prove that the surface passivation is more efficiently working by removing vulnerable defects on the surface. Hole and electron defect densities were reduced, leading to the highest power conversion efficiency of 22.6%. In addition, it can effectively protect the perovskite thin film and improve the operational stabilities in high thermal (85 °C) and humid conditions (50% relative humidity), suggesting a strong stability of the surface passivation layer.

Morphology and Performance Enhancement through the Strong Passivation Effect of Amphoteric Ions in Tin‐based Perovskite Solar Cells

“…In contrast to the control perovskite, the NH 3 +, and C=O stretching peaks were slightly shifted, likely a result of interactions between the oxygen in the carboxyl group and tin. [24,25] This observation implies that l-Asn zwitterion in tin perovskites can introduce nucleation sites, retard the crystallization rate and induce vertical crystal orientation, leading to the improved crystal quality of perovskite films.…”

Promoting Large-Area Slot-Die-Coated Perovskite Solar Cell Performance and Reproducibility by Acid-Based Sulfono-γ-AApeptide

“…Ji et al reported difunctionalized BTZI-TPA-passivated perovskite with a champion PCE of 24.06%, where the molecule formed a stronger interaction with uncoordinated Pb 2+ on the perovskite surface; consequently, the non-radiative recombination of the perovskite was significantly reduced . −COO–, −C­(NH)­NH 2 functional group-containing (α-methylguanido)­acetic acid-passivated (FAPbI 3 ) 0.95 (MAPbBr 3 ) 0.05 produced a maximum PCE of 22.6% . Post-treatment of Cs 0.03 (FA 0.90 MA 0.10 ) 0.97 PbI 3 by 2D oleylammonium iodide-based passivation demonstrated more than 24% PCE .…”

“…34 −COO−, −C(�NH)NH 2 functional group-containing (αm e t h y l g u a n i d o ) a c e t i c a c i d -p a s s i v a t e d ( F A P -bI 3 ) 0.95 (MAPbBr 3 ) 0.05 produced a maximum PCE of 22.6%. 35 Post-treatment of Cs 0.03 (FA 0.90 MA 0.10 ) 0.97 PbI 3 by 2D oleylammonium iodide-based passivation demonstrated more than 24% PCE. 36 Additionally, 3-(trifluoromethyl)phenethylamine hydroiodide (CF 3 PEAI) was employed for post-surface passivation, where it coordinated with the uncoordinated Pb 2+ and modified defects.…”

Ultrabroadband Emission from CsCu2I3/Cs3Cu2I5 Dual-Phase Glass-Ceramics with Long-Term Stability

“…1−6 However, their instability toward water, humidity, high temperature, and strong light irradiation, and, in addition, the toxicity of certain elements, such as lead, limit their applications. Factually, their stability has been improved substantially by many methods including surface passivation with an organic or inorganic shell, 7,8 encapsulation by a polymer, 8−10 lattice site substitution, 11 etc. Recently, researchers have generated considerable interest in glass-ceramics in order to address the instability of MHs.…”