Solution-Processed\nNb:SnO₂ Electron Transport\nLayer for Efficient Planar Perovskite Solar Cells

Abstract

Electron transport\nlayer (ETL), facilitating charge carrier separation\nand electron extraction, is a key component in planar perovskite solar\ncells (PSCs). We developed an effective ETL using low-temperature\nsolution-processed Nb-doped SnO₂ (Nb:SnO₂).\nCompared to the pristine SnO₂, the power conversion efficiency\nof PSCs based on Nb:SnO₂ ETL is raised to 17.57% from 15.13%.\nThe splendid performance is attributed to the excellent optical and\nelectronic properties of the Nb:SnO₂ material, such as\nsmooth surface, high electron mobility, appropriate electrical conductivity,\ntherefore making a better growth platform for a high quality perovskite\nabsorber layer. Experimental analyses reveal that the Nb:SnO₂ ETL significantly enhances the electron extraction and effectively\nsuppresses charge recombination, leading to improved solar cell performance.