Additive-Induced Film Morphology Evolution for Inverted Dion–Jacobson Quasi-Two-Dimensional Perovskite Solar Cells with Enhanced Performance

Abstract

In the past decade, three-dimensional (3D) perovskites have been under intense study. However, these devices always suffer from severe performance degradation. Recently, two-dimensional (2D) perovskites have attracted increasing attention due to their excellent environmental stability, but their low power conversion efficiency (PCE) limits their application. Therefore, many strategies have been applied to manipulate the crystallization and suppress the defects and low-n value phases. Additive engineering, as one of the most effective methods to achieve the above-mentioned goals, has been extensively studied. In this contribution, thiourea (TU) and methylammonium chloride (MACl) are successfully employed to contribute synergistically to optimize the crystallization process, leading to an enlarged grain size, smooth and dense surface morphology, and suppressed distribution of n values for improved phase purity. As a result, the optimized inverted Dion−Jacobson (DJ) 2D perovskite solar cell (PSC) device delivers an elevated PCE of 12.16% with a significantly improved short-circuit current density (J SC ) of 18.78 mA cm −2 and fill factor (FF) of 62.70%. In addition, the optimized devices show good environmental stability when exposed to ambient air.

Additive Engineering for Stable and Efficient Dion–Jacobson Phase Perovskite Solar Cells

“…As a result, out-of-plane oriented crystallization and ordered phase distribution are achieved. The thiourea (TU) [ 176 ] is positively utilized to make great efforts in optimizing the crystallization development, resulting in an increased grain size, flat and dense surface structure, and controlled delivery of n values for enhanced phase purity (Fig. 13 ).…”

The rise of quasi-2D Dion–Jacobson perovskites for photovoltaics

“…Min et al also employed thiourea and MACl to synergistically facilitate the crystallization process, which resulted in a smooth and dense surface morphology, and improved phase purity. 130 Chen et al reported well-oriented PDA-based DJ perovskite films synthesized using FACl additive. 97 Fig.…”

Multilateral Passivation Strategy in Post-Synthetic Flexible Metal–Organic Frameworks for Enhancing Perovskite Solar Cells

“…As an illustrative instance, in the context of planar n-i-p PSCs, the utilization of NiO@C nanoparticles as a highly effective interference layer, wherein their application successfully diminished the surface defects in the perovskite layer and facilitated improved charge transfer mechanisms . Recently, the additive engineering approach has proven to be an effective method in passivating surface defects or grain boundary defects of perovskite and facilitating homogeneous nucleation, thereby improving the stability of perovskite films. − …”