Mixed-Phase Low-Dimensional Perovskite-Assisted Interfacial Lead Directional Management for Stable Perovskite Solar Cells with Efficiency over 24%

The efficiency and stability of perovskite solar cells are affected by the Pb-I antisite and uncoordinated Pb-0 defects existing at the interface. Directional management of Pb-based defects can reduce the defect density and voltage loss. In this work, to settle the Pb-based defects at the interface for further stabilization of the perovskite surface, we propose the strategy of designing a low-dimensional perovskite (LDP) by an amphoteric heterocyclic cation which can increase the defect formation energies and inhibit the generation of Pb-I antisite defects. The growth of the mixed-phase LDP can introduce a strong interaction with under-coordinated Pb2+ upon the surface of peroskite films accomplished with the ability of dealing with different types of surface-terminating ends. The modified devices showed an increased efficiency of 24.07% (stabilized efficiency of 23.25%) as well as improved overall stability. This opens up a direction for prompting the practical application of perovskite photovoltaic devices based on the directional management of Pb-based interface defects.

Automated summary

The study successfully tackled the impact of Pb-based defects on the efficiency and stability of perovskite solar cells by designing a low-dimensional perovskite (LDP) using an amphoteric heterocyclic cation. This approach led to increased efficiency and overall stability of the devices, opening up new possibilities for practical application in the field of perovskite photovoltaic devices through directional management of Pb-based interface defects.