Enhance the performance of ZnO-based perovskite solar cells under ambient conditions

• Published in: Optical materials 2019-03, Vol.89, p.375-381
• Main Authors: Wang, Huan, Zhang, Xiaoshan, Huang, Tianjiao, Lu, Zuizhi, Gao, Fangfang, Shi, Zhongfeng, Zhou, Liya, Li, Rongguan, Tang, Guo
• Format: Article
• Language: English
• Subjects: MAI IPA/n-hexane solution; Perovskite solar cell; Photovoltaic performance; ZnO seed layer
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2019.01.059

The ETL layer is used to transport electrons and block holes in the perovskite solar cell (PSC), and the uniformity of the dense layer affects the open circuit voltage (Voc) of the battery. The PSC open circuit voltage prepared by the solution method was 0.68 V, and the open circuit voltage of the PSC prepared by the sol method was remarkably improved to 0.95 V. The quality of the perovskite layer is critical for obtaining high-performance perovskite solar cells (PSC). In the process of preparing PSC by sequential deposition, the MAI solution was formed by IPA-n-hexane instead of isopropyl alcohol (IPA) as a solvent to grow CH3NH3PbI3(MAPI). The MAPI prepared by the mixed solvent was characterized by scanning electron microscopy (SEM). The mixed solvent inhibited the Oswald ripening process, and the perovskite layer showed a uniform and dense morphology. The PL characterization implied that the MAPI film with low defect concentration, which prepared from the mixed solvent. Compared to the single solvent PSC (PCE = 4.2%), the efficiency was significantly improved by 1.5 times to 6.2%. This study provides the possibility to prepare ZnO-based high-efficiency solar cell devices in the air. [Display omitted] •The ZnO dense layer was prepared by sol method and assembled into a perovskite solar cell with Voc of 0.95V.•In the two-step deposition process, the second step was to prepare MAPbI3 using IPA-n-hexane as a mixed solvent.•The mixed solvent inhibits the Oswald ripening process resulting in a high-quality perovskite layer.•The trap state density in the PSC prepared by the mixed solvent was lowered, and the PCE reached 6.2%.