Sputtered WOx thin film as the electron transport layer for efficient perovskite solar cells

The electron transport layer (ETL) is critical in perovskite solar cells (PSCs) as it controls the optics of the complete solar cell. This study uses an industrially viable RF magnetron sputtering technique to prepare the tungsten oxide (WOx) ETL for PSCs. Necessary morphological and optoelectronic investigations were carried out to ensure the high-quality WOx thin-film. The influence of the deposition power on the ETL thickness and PSC optics were systematically investigated. A three-dimensional (3D) finite-difference time-domain (FDTD) approach analyses the optics and optimization of the complete solar cell. The investigations allow the optimized planar PSC to determine the J(SC) of> 21 mA/cm(2). The optical performance of the planar device is limited due to higher optical losses; hence, the current study proposes a PSC design embedded with Ag nanoparticles. The proposed PSC can improve the J(SC) by similar to 17% (up to 24.5 mA/cm(2)) than the planar device owing to improved light trapping, further boosting the PSC's energy conversion efficiency (ECE). A detailed discussion on film realization and solar cell optics is provided.