Cerium Acetylacetonate Interfacial Buffer Layer for Inverted Perovskite Solar Cells

doi:10.15541/jim20260112

Abstract

Abstract: Inverted perovskite solar cells (PSCs) have garnered significant attention due to their rapidly increasing efficiency, low-temperature fabrication process, and low cost. However, solution-processed tin oxide (SnO₂) electron transport layers (ETLs) often suffer from surface pinholes and poor interfacial contact, which aggravate interfacial non-radiative recombination and limit further performance improvement. In this work, cerium acetylacetonate (Ce(acac)₃) was introduced as an interfacial buffer layer between the solution-processed SnO₂ ETL and the Ag electrode. Ce(acac)₃ effectively covers and planarizes the SnO₂ surface, forming a continuous and dense interfacial layer. Furthermore, the modified SnO₂ films exhibit a decreased work function, leading to a reduced electron extraction barrier at the interface. This effectively suppresses non-radiative recombination and optimizes charge carrier extraction and transport. Consequently, the power conversion efficiency (PCE) of the PSC is enhanced from 20.33% to 22.85%, outperforming the conventional bathocuproine (BCP) buffer layer-based device (20.95%). Moreover, unencapsulated devices retain over 85% of the initial efficiency after 1000 h of storage in ambient air. This work demonstrates that introducing Ce(acac)₃ as an inorganic interfacial buffer layer enables optimization of interfacial morphology and chemical properties, paving the way for fabricating fully solution‑processed, highly efficient and stable inverted PSCs.

Key words: inverted perovskite solar cell, cerium acetylacetonate, SnO₂ electron transport layer, interfacial buffer layer

CLC Number:

TQ174

XIE Xinqian, HONG Xiang, YANG Songwang. Cerium Acetylacetonate Interfacial Buffer Layer for Inverted Perovskite Solar Cells[J]. Journal of Inorganic Materials, DOI: 10.15541/jim20260112.

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