Dual‐Functional Quantum Dot Seeding Growth of High‐Quality Air‐Processed CsPbI2Br Film for Carbon‐Based Perovskite Solar Cells. Issue 4 (14th January 2022)

• Record Type: Journal Article
• Authors: Xu, Shuaihang; Kang, Cuiting; Huang, Zhaoshuai; Zhang, Zhengyan; Rao, Huashang; Pan, Zhenxiao; Zhong, Xinhua
• Is Part Of: Solar RRL. Volume 6:Issue 4(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-14
• Subjects: all-inorganic perovskites -- carbon electrodes -- ligands -- quantum dot additives -- solar cells; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202100989
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : The high‐quality perovskite film is a prerequisite for high‐performance optoelectronic devices. Herein, CdSe colloidal quantum dots (QDs) serve as crystallization seeds for the first time to modulate the nucleation and crystal growth processes simultaneously of the CsPbI2 Br film in the ambient environment. As additives, CdSe QDs help promote the nucleation process in the initial stage of perovskite formation. In addition, it is revealed that the surface ligands of QDs also have an essential influence on the subsequent crystal growth of the perovskite film. The bifunctional ligands on the surface of QDs are beneficial in delaying the growth process of perovskite due to the free functional groups at the ends. The CsPbI2 Br film prepared with bifunctional organic ligand‐capped CdSe QD additives shows better crystallinity than that of the inorganic ligand‐based one due to the dual function of these kinds of QDs in not only promoting nucleation but also retarding crystal growth of CsPbI2 Br crystals. As a result, the high‐quality CsPbI2 Br film with a low defect state density is prepared in the ambient environment. The optimized efficiency of the assembled hole‐conductor‐free carbon‐based perovskite solar cells (C‐PSCs) is increased from 12.73% to 14.49%, which is one of the best results for all‐inorganic C‐PSCs. Abstract : CdSe quantum dots (QDs) are used to modulate the crystallization of CsPbI2 Br films in air. The added QDs with bifunctional ligands play a dual role in not only promoting the nucleation process but also retarding the crystal growth of CsPbI2 Br. Finally, the efficiency of carbon‐based CsPbI2 Br solar cells is increased from 12.73% to 14.49%, benefitting from the improved film quality.