Boosting the Performance of Perovskite Solar Cells through Systematic Investigation of the Annealing Effect of E-Beam Evaporated TiO2

Abstract

Electron transport layer (ETL) plays an undeniable role in improving the performance of n-i-p planar perovskite solar cells (PSCs). Titanium dioxide (TiO2) is known as a promising ETL material for perovskite solar cell. In this work, the effect of annealing temperature on optical, electrical, and surface morphology of the electron-beam (EB)-evaporated TiO2 ETL, and consequently on the performance of perovskite solar cell, was investigated. It was found that annealing treatment at an optimized temperature of 480 °C considerably improved the surface smoothness, density of grain boundaries, and carrier mobility of TiO2 film, which resulted in nearly 10-fold improvement in power conversion efficiency (11.16%) in comparison with the unannealed device (1.08%). The improvement in performance of the optimized PSC is attributed to the acceleration of charge carrier extraction, as well as suppression of the recombination at the ETL/Perovskite interface.

Exploring fullerene derivatives for optoelectronic applications: synthesis and characterization study

“…The dihydrofuran-fused C 60 fullerene derivatives with sugar units (13,14,15) were synthesized following the procedure outlined in Scheme 1. The incorporation of sugar units was intended to enhance solubility and explore their interaction with the substrate, which is fluorine-doped tin oxide (FTO).…”

“…Among the contenders, titanium dioxide (TiO 2 ) has held a prominent position due to its electron transport capabilities; however, it has been marred by challenges linked to high-temperature processing and potential electrical instabilities. 14 Amidst these challenges, a remarkable contender has risen to prominence -fullerenes, particularly fullerene derivatives, which have exhibited a level of resilience and enduring performance that justifies their characterization as ''immortal'' within the realm of PSCs. 15 Advancement in fullerene chemistry 16 and the synthesis of various solution-processable derivatives have propelled their widespread adoption as key components in various electronic devices.…”

Recent Advances in the Photonic Curing of the Hole Transport Layer, the Electron Transport Layer, and the Perovskite Layers to Improve the Performance of Perovskite Solar Cells

“…However, its crystallization into a compact layer requires a high temperature (400-500 °C) [22,23], which is not compatible with certain PSC configurations (p-i-n) or with flexible plastic-based substrates (kapton, polyethylene terephthalate (PET), poly-ethylene naphthalate (PEN)). To overcome these issues, various approaches have been developed for fabricating compact TiO 2 coatings for PSCs, such as sputtering process [24,25], which showed power conversion efficiencies (PCEs) of 16.1% and 23% on glass substrates; electron beam evaporation [26], demonstrating 11.6%; and solution treatment methods, involving a lower temperature of 150 • C, which resulted in a PCE of 13.5% [27]. In contrast to these techniques, the PC of TiO 2 is promising mainly because of its compatibility with R2R and sensitive substrates (PEN, PET) [28], Additionally, its reduced process time and low thermal budgets [29] make it appealing for large-scale industry.…”