The Impact of MAPbI3 Quantum Dots on CsFA Perovskite Solar Cells: Interface and Hole Extraction Improvement

Perovskite solar cells (PSCs) are at the forefront of photovoltaic technology due to their high efficiency. However, their commercialization faces a major challenge in stability. The interface between the charge-carrying layers and the perovskite film is vital in determining both stability and efficiency. To address these issues, we focus on CH3NH3PbI3 (MAPbI3) quantum dots (QDs), synthesized via a cost-effective ligand-assisted reprecipitation (LARP) method at room temperature. By optimizing the spin-coating speed, we tailored the thickness of the MAPbI3 QD films, thereby enhancing the interface between the hole transport layer (HTL) and the pristine perovskite film. These QD films serve as passivation layers, enhancing the performance of PSC devices structured as FTO/TiO2–NPs/Cs0.17FA0.83Pb(I0.83Br0.17)3/MAPbI3 QDs/Spiro-OMeTAD/Carbon. Devices fabricated with a spin speed of 4000 rpm exhibited superior performance, achieving a fill factor (FF) of 72.58%, a short-circuit current density (Jsc) of 20.65 mA/cm2, an open-circuit voltage (Voc) of 1.08 V, and a power conversion efficiency (PCE) of 16.11%, attributed to improved hole extraction efficiency.