Efficiency and Stability Enhancement of Fully Ambient Air Processed Perovskite Solar Cells Using TiO 2 Paste with Tunable Pore Structure

• Published in: Advanced materials interfaces Vol. 7; no. 3
• Main Authors: Seyed‐Talebi, Seyedeh Mozhgan, Kazeminezhad, Iraj, Shahbazi, Saeed, Diau, Eric Wei‐Guang
• Format: Journal Article
• Language: English
• Published: 01.02.2020
• ISSN: 2196-7350; 2196-7350
• DOI: 10.1002/admi.201900939

Abstract Crystallization and nucleation of the perovskite layer in the mesoscopic perovskite solar cells (PSCs) depend on the nucleation sites of the electron transport layer (ETL). The porosity optimization of TiO 2 film as an efficient ETL plays an important role in the performance improvement of PSCs. In the present study, nontoxic carbon spheres synthesized with uniform morphology and controllable size under hydrothermal conditions and used as a template to generate the tunable porous TiO 2 films. Furthermore, the effect of porosity modification of TiO 2 on the formation of perovskite films with large grain size is studied in an ambient atmosphere with humidity higher than 50%. The best TiO 2 film is produced with carbon spheres 8 wt% (C8), which results in the formation of a pinhole‐free, and compact‐packed perovskite layer. The fully air processed PSC device with the ETL made of C8 film exhibits an efficiency of 16.66% with reduced hysteresis, which is much superior in performance compared to the standard cell (11.72%). It is believed that this porosity optimization of TiO 2 layer is a simple practical strategy for improved stability of fully air processed efficient perovskite solar cells and usable for the fabrication of reproducible compact perovskite layers in uncontrolled laboratories.