Enhanced charge extraction in carbon-based all-inorganic CsPbBr3 perovskite solar cells by dual-function interface engineering. (20th December 2019)

• Record Type: Journal Article
• Authors: Su, Guodong; He, Benlin; Gong, Zekun; Ding, Yang; Duan, Jialong; Zhao, Yuanyuan; Chen, Haiyan; Tang, Qunwei
• Is Part Of: Electrochimica acta. Volume 328(2019)
• Publication Date: 2019-12-20
• Subjects: All-inorganic CsPbBr3 perovskite solar cells -- Interface engineering -- CsPbBrxI3-x nanocrystals -- Solvent treatment -- Charge extraction; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2019.135102
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Carbon-based all-inorganic CsPbBr3 perovskite solar cells (PSCs) have attracted growing interests due to low cost and excellent tolerances toward moisture, temperature, oxygen and ultraviolet light. However, carrier recombination of CsPbBr3 film and large energy level differences at CsPbBr3 /carbon interface are still the most crucial problem for further enhancement of power conversion efficiency. In the current study, an intermediate energy level at CsPbBr3 /carbon interface and CsPbBr3 film passivation are employed by coating hexane solution of CsPbBrx I3-x nanocrystals (NCs) on the perovskite layer. Through systematic study on interfacial engineering, it is found that CsPbBrx I3-x NCs with tunable energy level can remarkably reduce energy loss and hexane under passivation treatment can enlarge perovskite grain size as well as reduce trap state density. A champion power conversion efficiency of 9.45% is achieved for CsPbI3 NCs tailored all-inorganic CsPbBr3 PSC in comparison with 5.26% for NCs-free device, with the unencapsulated carbon-based CsPbBr3 PSC exhibiting remarkable long-term stability over 900 h in 80% relative humidity air atmosphere at 25 °C. This work provides an effective approach to promote charge extraction and reduce defect states density as well as enhance the performance of PSCs. Graphical abstract: Image 1 Highlights: Dual-function interface engineering are developed to promote charge extraction. High-quality CsPbBr3 film and the reduced energy loss are realized simultaneously. CsPbBr3 PSC tailored with CsPbI3 NCs achieves a champion PCE of 9.45%. All-inorganic CsPbBr3 PSC free of encapsulation exhibits excellent stability.