Controlling surface morphology of Ag-doped ZnO as a buffer layer by dispersion engineering in planar perovskite solar cells

Ghazaleh Bagha; Katayoon Samavati; Homam Naffakh-Moosavy; Laleh Farhang Matin

doi:10.1038/s41598-024-55379-w

Controlling surface morphology of Ag-doped ZnO as a buffer layer by dispersion engineering in planar perovskite solar cells

Sci Rep. 2024 Feb 26;14(1):4617. doi: 10.1038/s41598-024-55379-w.

Authors

Ghazaleh Bagha¹, Katayoon Samavati², Homam Naffakh-Moosavy³, Laleh Farhang Matin¹

Affiliations

¹ Department of Physics, North Tehran Branch, Islamic Azad University, Tehran, Iran.
² Department of Physics, North Tehran Branch, Islamic Azad University, Tehran, Iran. k_samavati@iau-tnb.ac.ir.
³ Department of Materials Engineering, Tarbiat Modares University (TMU), P.O. Box 14115-143, Tehran, Iran.

Abstract

In recent years, the power conversion efficiency (PCE (%)) of perovskite solar cells (PSCs) has improved to over 26%. To enhance the photovoltaic properties of PSCs, several materials for the electron transport layer (ETL) have been investigated. Zinc oxide (ZnO) is a significant ETL due to its high electron mobility and optical transparency in PSCs. As a result of various deposition methods, ZnO ETL can be processed at low temperatures. On the other hand, based on several studies, metal-doped ZnO can facilitate electron transfer, thereby improving the performance of un-doped ZnO ETL-based PSCs. Here, to improve the PCE (%) and long-term stability of un-doped ZnO ETL-PSCs, silver (Ag)-doped ZnO 1wt% as a buffer layer is examined. In this paper, with the addition of an organic solvent (ethanol) to the dispersion of Ag-doped ZnO 1 wt% nanoparticles (NPs) in deionized (DI) water, the morphology of the buffer layer (Ag-doped ZnO 1 wt%) can be controlled. This approach focuses on reducing the wettability of the ZnO/Ag-doped ZnO 1 wt% bilayer ETLs and enhancing the stability of un-doped ZnO ETL-PSCs. According to the results, the ZnO/H₂O-ethanol mixtures-Ag-doped ZnO 1 wt% bilayer ETL leads to the formation of high-quality perovskite with low defects, reducing the recombination rate, and long-term stability of un-doped ZnO ETL-PSCs in ambient conditions.

Keywords: Buffer layer; Dispersion; Electron transport layer; Water–ethanol mixtures; ZnO.