Defect Management and Ion Infiltration Barrier Enable High-Performance Perovskite Solar Cells

Abstract

The stability of perovskite solar cells (PSCs) has been considered as one of the major obstacles toward practical application. Defects in the perovskite layer and ion infiltration from the hole transport layer (HTL) can trigger degradation of n-i-p PSCs. Herein, phenylhydrazine-4-sulfonic acid (PHPA) was employed as an additive to modulate perovskite crystallization during film formation, enlarging the perovskite crystal grain sizes to ∼3 μm. Density functional theory (DFT) calculations revealed that PHPA could effectively inhibit the formation of iodine vacancies (V I ) and passivate the under-coordinated Pb 2+ ions. Additionally, perfluorooctanoic acid (PFOA) was adopted to passivate the surface located dangling Pb 2+ defects, improve the surface hydrophobicity, and inhibit Li + ion migration from the HTL to the bottom perovskite, thus enhancing the device's environmental and operational stability. Consequently, the resulting devices delivered a champion efficiency of 25.1% with an excellent maximum-power-point (MPP) tracking stability.

Enhancing Performance and Stability of p-i-n Perovskite Solar Cells with Ag–Cu Codeposited Alloy Electrodes

“…Perovskite solar cells (PSCs) have emerged as a leading direction in future clean energy production due to their excellent photovoltaic performance, low-temperature and environmentally friendly preparation methods, and cost-effective raw materials. , After years of extensive research and development, the photoelectric performance of PSCs has made significant strides, achieving an impressive conversion efficiency of 26.14%. , Enhancement of stability is an indispensable aspect for the commercialization of perovskite solar cells. , Factors such as oxygen, moisture, and heat lead to the degradation of perovskite and have been the focal points of research in recent years. − Additionally, there is growing attention toward the mechanism of decreased stability in the perovskite solar cells due to ion migration between the electrode and the perovskite. , …”