Pre-Embedded Potassium Acetate-Modified SnO2 Electron Transfer Layer for Efficient and Durable Perovskite Solar Cells

Lina Qin; Mengfei Zhu; Min Zhang; Junchuan Liang; Xingkai Ma; Pengbo Zhang; Daocheng Hong; Yaoda Wang; Yuxi Tian; Huapeng Sun; Zuoxiu Tie; Yan Xiong; Zhong Jin

doi:10.1021/acs.nanolett.5c00932

Pre-Embedded Potassium Acetate-Modified SnO₂ Electron Transfer Layer for Efficient and Durable Perovskite Solar Cells

Nano Lett. 2025 Apr 30;25(17):7053-7060. doi: 10.1021/acs.nanolett.5c00932. Epub 2025 Apr 16.

Authors

Lina Qin¹, Mengfei Zhu¹, Min Zhang¹, Junchuan Liang¹, Xingkai Ma¹, Pengbo Zhang¹, Daocheng Hong¹, Yaoda Wang¹, Yuxi Tian¹, Huapeng Sun², Zuoxiu Tie^{1

3}, Yan Xiong¹, Zhong Jin^{1

3}

Affiliations

¹ State Key Laboratory of Coordination Chemistry, MOE Key Laboratory of Mesoscopic Chemistry, MOE Key Laboratory of High Performance Polymer Materials and Technology, Jiangsu Key Laboratory of Advanced Organic Materials, Suzhou Key Laboratory of Green Intelligent Manufacturing of New Energy Materials and Devices, Tianchang New Materials and Energy Technology Research Center, Institute of Green Chemistry and Engineering, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China.
² School of New Energy, Chenjiang Laboratory, Chenzhou Vocational Technical College, Chenzhou, Hunan 423000, P. R. China.
³ Suzhou Tierui New Energy Technology Co., Ltd., Suzhou, Jiangsu 215228, P. R. China.

PMID: 40241299
DOI: 10.1021/acs.nanolett.5c00932

Abstract

Perovskite solar cells (PSCs) have garnered significant attention due to their exceptional photovoltaic performances. However, their power conversion efficiency and stability are significantly hindered by lattice defects and nonradiative recombination losses at the interface between the perovskite film and electron transport layer (ETL). Herein, we report the incorporation of multifunctional potassium acetate (KAc) into SnO₂ ETL. Through thermal diffusion of K⁺ and CH₃COO^- during annealing, these ions electrostatically penetrate the surface and grain boundary, effectively passivating the formation of bulk defects. The resulting KAc-SnO₂ ETL exhibited uniformity, low defect density, and high conductivity, providing an ideal ETL film for the subsequent deposition of perovskite films, thereby enhancing interfacial charge transfer and device efficiency. The optimized device achieved a PCE of 21.76%, a 14% increase over the control device (19.16%), and retained 88.9% of its initial PCE after 1000 h, offering a promising approach for scalable manufacturing in the perovskite industry.

Keywords: SnO2 electron transport layer; crystalline and interfacial engineering; highly conductive buffer layer; multifunctional potassium acetate (KAc) additive; organic−inorganic hybrid perovskite solar cells.