Multiple Function Synchronous Optimization by PbS Quantum Dots for Highly Stable Planar Perovskite Solar Cells with Efficiency Exceeding 23%. (29th January 2023)

• Record Type: Journal Article
• Authors: He, Li; Su, Hongzhen; Li, Zhengping; Liu, Hong; Shen, Wenzhong
• Is Part Of: Advanced functional materials. Volume 33:Number 17(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-01-29
• Subjects: colloidal lead sulfide quantum dots -- electrical conductivity -- near‐infrared region -- perovskite solar cells -- stability; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202213963
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Colloidal lead sulfide (PbS) quantum dots (QDs), which possess quantum confinement effect and processing compatibility with perovskite, are regarded as an excellent material for optimizing perovskite solar cells (PSCs). However, the existing PSCs optimized by PbS QDs are still facing the challenges of poor performance of the charge transport layers, low utilization in the near‐infrared (NIR) region, and unsuitable energy level alignment, which limit the improvement of power conversion efficiency (PCE). Herein, a synchronous optimization strategy is realized via simultaneously introducing PbS QDs into SnO2 electron transport layer and employing rare‐earth‐doped PbS QDs (Eu:PbS QDs) film with hydrophobic chain ligands as the NIR light‐absorping layer and hole transport layer (HTL) of devices. PbS QDs effectively decrease the density of trap states by passivating defects. Eu:PbS QDs film with adjustable bandgap is employed as an absorption layer to broaden the NIR spectral absorption. The well‐matched energy level between Eu:PbS QDs layer and perovskite layer implies efficient hole transfer at the interface. The successful synchronous optimization greatly elevates all photovoltaic parameters, reaching a maximum PCE of 23.27%. This PCE is the highest for PSCs utilizing PbS QDs material in recent years. The optimized PSCs retain long‐term moisture and light stability. Abstract : A synchronous optimization strategy is realized via simultaneously introducing PbS QDs into SnO2 electron transport layer and employing Eu:PbS QDs film with hydrophobic chain ligands as the NIR light‐absorping layer and hole transporting layer of devices simultaneously. The successful synchronous optimization greatly elevates all photovoltaic parameters, reaching a maximum power conversion efficiency of 23.27% with lower hysteresis.