Enhancing Performance and Stability of Sn–Pb Perovskite Solar Cells with Oriented Phenyl-C₆₁-Butyric Acid Methyl Ester Layer via High-Temperature Annealing

Abstract

Phenyl-C 61 -butyric acid methyl ester (PCBM) can be used as a passivation material in perovskite solar cells (PeSCs) in order to reduce the trap site of the perovskite. Here, we show that a thick PCBM layer can form a smoother surface on the SnO 2 substrate, improving the grain size and reducing the microstrain of the perovskite. High-temperature annealing treatment of PCBM layer not only increases its solvent resistance to perovskite precursor or antisolvent, but also enhances its molecular alignment, resulting in improved conductivity as an electron transport layer. High-temperature annealed PCBM (HT-PCBM) effectively minimizes trap-assisted nonradiative recombination by reducing trap density in perovskite and improving the electrical properties at the interface between SnO 2 and perovskite layers. This HT-PCBM process significantly enhances the performance of the PeSCs, including the open-circuit voltage (V OC ) from 0.39 to 0.77 V, fill factor from 52% to 65%, and power conversion efficiency (PCE) from 6.03% to 15.50%, representing substantial improvements compared to devices without PCBM. This PCE is the highest efficiency among conventional (n-i-p) Sn−Pb PeSCs reported to date. Moreover, passivating the trap sites of SnO 2 and separating the interface between the Sn-containing perovskite and the substrate effectively have improved the stability of the Sn−Pb perovskite in the n-i-p structure. The optimized best device with HT-PCBM has maintained an efficiency of over 90% for more than 300 h at 85 °C and 5000 h at room temperature in a glovebox atmosphere.

Crystallinity Control and Strain Release in Wide-Bandgap Perovskite Film via Seed-Induced Growth for Efficient Photovoltaics

“…From Figure d, it can be seen that the ideal factor n is 1.59 ± 0.04, 1.78 ± 0.03, and 1.81 ± 0.05 for IPA-, CB-, and EA-modified PSCs, respectively, compared to the 1.84 ± 0.04 of the control device. Indicating reduced nonradiative recombination loss in the ACSM. , …”

The dawn of MXene duo: revolutionizing perovskite solar cells with MXenes through computational and experimental methods

“…In terms of efficiency, however, the mesoporous structure prevails over the planar shape. 46 Regarding fabrication, the planar structure has an advantage over the mesoscopic structure since it can be made at a lower temperature. 47 The schematic diagram of various PSC architecture is depicted in Fig.…”

Chelating Dual Interface for Efficient and Stable Crystal Growth and Iodine Defect Management in Sn–Pb Perovskite Solar Cells

“…Sn–Pb perovskite solar cells (PSCs) with narrower band gaps hold great commercial potential in both single-junction and tandem devices as they can harness a broader range of solar spectrum. − Over the past ten years, Sn–Pb PSCs have made important progress in power conversion efficiency (PCE), skyrocketing from 4.18 to 23.8% . However, compared to pure lead PSCs, Sn–Pb PSCs still lag in efficiency and stability. − Two main factors cause this lag: first, compared to Pb 2+ , Sn 2+ in Sn–Pb PVK possesses a lower chemical potential, , making it prone to be oxidized into Sn 4+ . This oxidation process generates a large number of tin vacancies in the films, resulting in self P-doping , and significantly shortened carrier lifetime .…”