Enhanced fill factor for normal n‐i‐p planar heterojunction and mesoscopic perovskite solar cells using ruthenium‐doped TiO₂ electron transporting layer

Abstract

Perovskite solar cells (PSCs) fabricated with a normal mesoscopic negative‐intrinsic‐positive (n‐i‐p) device structure have shown a great promise for further developments ever since their enhanced performance with high power conversion efficiency (PCE, 25.2%) and excellent reproducibility. The electron transporting layer (ETL) employed in such PSCs has been a critical component for improving their performance. The present work focuses on the synthesis of high‐quality Ru‐doped compact TiO2 (c‐TiO2) ETLs (Ru:c‐TiO2) by a simple spin‐coating technique. Further, the role of Ru4+ cation doping in c‐TiO2 is discussed in detail. A systematic study revealed that the Ru‐doping not only significantly influences the open‐circuit voltage (Voc), current density (Jsc), and fill factor (FF) but also suppresses the charge recombination in the perovskite devices. The PSCs prepared using Ru‐c‐TiO2 ETLs with optimum Ru‐doping content exhibited PCEs of 19.48% for planar and 20.87% for mesoscopic device architecture with enhanced photovoltage. Additionally, the fabricated PSC devices based on 1.5% Ru:c‐TiO2 ETLs exhibited air stability over 200 days, which is much higher than that of a control device.

Interfacial band offset engineering with barium-doping towards enhanced performance of all inorganic CsPbI2Br perovskite solar cells

“…TiCl 4 treatment was carried from an aqueous TiCl 4 solution followed by sintering at 450 1C for 30 min. 35,36…”

Charge transport materials for mesoscopic perovskite solar cells

“…Ru 4+ cation doping of TiO 2 also suppressed charge recombination and improved electron transport leading upon precise doping optimization and Ru 4+ substituted Ti 4+ to PCEs of 20.87% and a much improved air PSC stability of over 200 days. 60 Recently, Chen et al synthesized mesoscopic Ag-doped TiO 2 NPs of various concentrations by a sol–gel and hydrothermal procedure and applied them as ETLs in mp-PSCs. 61 The optimized device with 1 mol% meso-Ag:TiO 2 showed the highest PCE value attributed to the improved electron mobility of the Ag-doped TiO 2 layer.…”

Zinc-Tin-Oxide Composite Films as an Alternate Electron Transport Layer in Perovskite Solar Cell

“…3 Perovskite solar cell (PSC) is a cost-effective solar energy harvesting technology because of its facile way of fabrication and efficient solar power conversion compared to other technology. 4 PSC technology is an effective way to develop a flexible energy source for wearable devices. 5 Additionally, from the material point of view, perovskite material possesses unique properties like high absorption coefficients across the visible spectrum.…”

“…5 Additionally, from the material point of view, perovskite material possesses unique properties like high absorption coefficients across the visible spectrum. 4 The bandgap of the perovskite layer can be tuned by changing the material composition. 4 PSC fabrication advanced initially from 2013 to 2022 through materials engineering processes.…”

“…4 The bandgap of the perovskite layer can be tuned by changing the material composition. 4 PSC fabrication advanced initially from 2013 to 2022 through materials engineering processes. 6 As a result,…”