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Abstract Dimethylammonium lead iodide (DMAPbIx) has the potential to address the phase stability issue of inorganic perovskite solar cells (PSCs). In this study, the crystallinity, phase structure, defect states, and crystal growth habits of DMAPbIxare controlled by adjusting thexvalue during synthesis, where N,N‐dimethylacetamide (DMAC) is used as the solvent to regulate perovskite film growth. Furthermore, large‐area CsPbI2.85Br0.15perovskite films with preferred oriented growth are achieved using the optimizedxvalue in DMAPbIxthrough the slot‐die coating method. The inorganic PSCs, with a n‐i‐p structure and the active area of 0.04 cm2, achieve a champion power conversion efficiency (PCE) of 19.82%, with an open‐circuit voltage (Voc) of 1.16 V based on perovskite films formed by slot‐die coating. This work provides important insights into the DMAPbIx‐based method for fabricating high‐quality inorganic perovskite films, and paves the way for large‐area inorganic PSCs fabrication for practical applications.
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All‐Inorganic CsPbI 3 Quantum Dot Solar Cells with Efficiency over 16% by Defect Control
Abstract All‐inorganic CsPbI3quantum dots (QDs) have shown great potential in photovoltaic applications. However, their performance has been limited by defects and phase stability. Herein, an anion/cation synergy strategy to improve the structural stability of CsPbI3QDs and reduce the pivotal iodine vacancy (VI) defect states is proposed. The Zn‐doped CsPbI3(Zn:CsPbI3) QDs have been successfully synthesized employing ZnI2as the dopant to provide Zn2+and extra I−. Theoretical calculations and experimental results demonstrate that the Zn:CsPbI3QDs show better thermodynamic stability and higher photoluminescence quantum yield (PLQY) compared to the pristine CsPbI3QDs. The doping of Zn in CsPbI3QDs increases the formation energy and Goldschmidt tolerance factor, thereby improving the thermodynamic stability. The additional I−helps to reduce theVIdefects during the synthesis of CsPbI3QDs, resulting in the higher PLQY. More importantly, the synergistic effect of Zn2+and I−in CsPbI3QDs can prevent the iodine loss during the fabrication of CsPbI3QD film, inhibiting the formation of newVIdefect states in the construction of solar cells. Consequently, the anion/cation synergy strategy affords the CsPbI3quantum dot solar cells (QDSC) a power conversion efficiency over 16%, which is among the best efficiencies for perovskite QDSCs.
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- Award ID(s):
- 1719797
- PAR ID:
- 10454387
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 31
- Issue:
- 4
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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