Recent advances of two-dimensional material additives in hybrid perovskite solar cells

Abstract

Perovskite solar cells (PSCs) have become one of the state-of-the-art photovoltaic technologies due to their facile solution-based fabrication processes combined with extremely high photovoltaic performance originating from excellent optoelectronic properties such as strong light absorption, high charge mobility, long free charge carrier diffusion length, and tunable direct bandgap. However, the poor intrinsic stability of hybrid perovskites under environmental stresses including light, heat, and moisture, which is often associated with high defect density in the perovskite, has limited the large-scale commercialization and deployment of PSCs. The use of process additives, which can be included in various subcomponent layers in the PSC, has been identified as one of the effective approaches that can address these issues and improve the photovoltaic performance. Among various additives that have been explored, two-dimensional (2D) materials have emerged recently due to their unique structures and properties that can enhance the photovoltaic performance and device stability by improving perovskite crystallization, defect passivation, and charge transport. Here, we provide a review of the recent progresses in 2D material additives for improving the PSC performance based on key representative 2D material systems, including graphene and its derivatives, transitional metal dichalcogenides, and black phosphorous, providing a useful guideline for further exploiting unique nanomaterial additives for more efficient and stable PSCs in the near future.

Interfacial Charge Transfer in Atomically Thin 2D Transition-Metal Dichalcogenide Heterostructures

“…To form heterostructures with TMDs, perovskites are typically spin coated, CVD grown or mechanically exfoliated on top of TMDs. TMD flakes have also been used as additives in perovskite devices, 72 however, we limit our discussions here to pure TMD and perovskite heterostructures.…”

Research on Preparation and Progress of Two-Dimensional Perovskite Solar Cells

“…Figure 1 shows the structure of two-dimensional perovskite solar cells. The efficiency of this kind of solar cells has been continuously broken through, but the liquid electrolyte used in this kind of solar cells will dissolve and decompose perovskite materials, making the internal light absorption layer extremely unstable, which leads to the extremely short life of the device [8]. Therefore, if we want to further improve the stability of solar cells, the key point is to find a substitute for liquid electrolyte.…”

Perovskenes: two-dimensional perovskite-type monolayer materials predicted by first-principles calculations

“…By decreasing the number of layers from a multilayer to a monolayer a transition from an indirect to a direct bandgap occurs in this class of materials which causes a significant enhancement of their electrical and optical characteristics such as their photoluminescence properties. [26][27][28][29][30][31][32] Therefore, going from the bulk to the 2D limit of atomically thin materials may bring more intriguing properties that may be important technologically.…”