Role of Metal Oxide Electron-Transport Layer Modification on the Stability of High Performing Perovskite Solar Cells

Organic–inorganic hybrid perovskite light absorbers have recently emerged as a “holy grail” for next generation thin‐film photovoltaics with excellent optoelectronics properties and low fabrication cost. In a very short span of time, we have witnessed a pronounced and unexpected progress in organic– inorganic perovskite solar cells (PSCs) with a vertical rise in power conversion efficiency from 3.8 to 22.1 %. In this manuscript we focus specifically on the recent development of metal oxide‐based electron‐transporting layer (ETL) modification for high performing PSCs and their stability. This review highlights various methodologies to modify existing compact/scaffold layers for improving device performance and stability. Various aspects of the ETL are discussed with different metal oxide compact layers in their relation to modification in mesoporous layers towards the design of a cell structure with high performance and stability. Dig deeper–Solution at the bottom! Recent developments of metal oxide‐based electron‐transporting layers (ETLs) for high performing, stable perovskite solar cells (PSCs) are reviewed. Various methodologies to modify existing ETLs, the first deposited layer in regular architecture PSCs, are highlighted, and the effects of these modifications are considered towards the design of a cell structure with high performance and stability.