Ammonium Thiocyanate-Passivated Quasi-Two-Dimensional Dion Jacobson Perovskite Solar Cells for Improved Efficiency and Stability

Abstract

Quasi-two-dimensional (quasi-2D) Dion Jacobson (D-J) layered perovskites have recently emerged as attractive photovoltaic materials due to their out-of-plane charge conduction and superior environmental stability. However, their power conversion efficiency (PCE) still needs to be optimized before these perovskites become competitive with their three-dimensional counterpart. Here, we report D-J phase quasi-2D (XDA)(MA)3(Pb)4(I)13 perovskites processed with an ammonium thiocyanate (NH4SCN) additive, showing a stabilized PCE of 17.05% which is one of the highest reported PCEs for a D-J phase quasi-2D perovskite. The NH4SCN additive modification leads to the optimum phase distribution, enlarged grain size, and improved crystallinity. Moreover, increased charge transport and reduced defect density was confirmed in the passivated perovskite. The unencapsulated device retained 80% of its initial PCE after 1000 h of storage under 50% relative humidity and 75% of its initial PCE in 200 h of storage under 85 °C of thermal stress. The synergistic use of NH4SCN with a di-ammonium cation in a quasi-2D perovskite offers new opportunities for the development of highly efficient perovskite solar cells with long-term operational stability.

Improved Efficiency and Stability in 1,5-Diaminonaphthalene Iodide-Passivated 2D/3D Perovskite Solar Cells

“…The pristine 3D perovskite-based device shows a slope of 1.68 k B T / e , which is further reduced to 1.32 k B T / e in the case of 2D/3D perovskite devices. This reduced value of slope n in case of 2D/3D PSCs indicates the suppressed defect-mediated nonradiative recombination owing to the improved film quality and decreased defect density …”

The Effect of the Alkyl Chains of the Alkylammonium Pesudohalide Additives on the Performance of Dion Jacobson Perovskite Solar Cells

“…In order to improve the quality of the DJ perovskite films, researchers have made attempts in manipulating the structures of the spacer cations, the composition of the small A cations, and the deposition methods and the additives. [24][25][26][27][28] In 2017, Kanatzidis et al reported a PCE ≈7% for the first examples of the DJHPSCs using 3-(Aminomethyl)piperidinium (3AMP) as the spacer cation. [11] One year later, authors from the same group improved the crystallinity of the perovskite film by using a mixture of FA and MA cations to construct the DJP film, obtaining a PCE of 12.04%.…”

“…In order to improve the quality of the DJ perovskite films, researchers have made attempts in manipulating the structures of the spacer cations, the composition of the small A cations, and the deposition methods and the additives. [ 24–28 ] In 2017, Kanatzidis et al. reported a PCE ≈7% for the first examples of the DJHPSCs using 3‐(Aminomethyl)piperidinium (3AMP) as the spacer cation.…”

Amplified spontaneous emission from waveguides based on hybrid quasi-2D perovskites of Dion–Jacobson and Ruddlesden–Popper phases

“…Compared to RP-type spacers, PDA 2+ , possessing a pair of ammonium at both ends of the carbon chain, can link two [MX 6 ] 4À layers within the monolayer through ionic bonds instead of van der Waals bonds. 36,37 Therefore, the connection of two sides of PDA 2+ can be strengthened and the consistency of crystallization improved, resulting in an optimized morphology. At the same time, the characteristic quasi-2D structure is reserved.…”