The Investigation for Coating Method of Titanium Dioxide Layer in Perovskite Solar Cells

Abstract

The effect of conventional Perovskite solar cells (PSCs) by using different concentration and spin-coating speeds of titanium dioxide (TiO2) as an electron transport layer (ETL) was studied. The influence of TiO2 based on device structure: fluorine-doped tin oxide substrate/TiO2/Perovskite (CH3NH3PbI3)/2,2′,7,7′-Tetrakis[N,N-di(4-methoxyp phenyl)amino]-9,9′-spirobifluorene/silver, is also studied. The spin-coating speed is varied in a range from 1000 to 3000 rpm to get optimal performance of device. The optimized power conversion efficiency (PCE) of PSCs with original concentration (OC) and double concentration (DC) TiO2 is 8.74 and 9.93%, respectively. The reason is attributed to excellent absorption in shorter wavelength, compact characteristic, and suitable thickness of TiO2, leading to perfect short-circuit current density (Jsc), lower series resistance (Rs), and higher fill factor (FF) of 0.75. Besides, recombination of electron and hole is also decreased due to the compact feature, leading to higher open-circuit voltage (VOC) of 0.91 V.

Graphite/Carbon Black Counter Electrode Deposition Methods to Improve the Efficiency and Stability of Hole-Transport-Layer-Free Perovskite Solar Cells

“…The presence of these peaks indicated the formation of a tetragonal phase in the perovskite crystal structure in the samples. − A very sharp peak could be observed at around 26.64°, corresponding to graphite’s basal (002) diffraction peak. Compared to FTO/TiO 2 /perovskite, the FTO/TiO 2 film only showed a small peak of TiO 2 at 25.5°, which represented the tetragonal anatase (101) structure of the mesoporous . The diffraction peaks (marked with asterisks) at 26.54, 33.74, 37.8, 51.78, 62.08, and 65.56° were attributed to the FTO substrate …”

“…Compared to FTO/ TiO 2 /perovskite, the FTO/TiO 2 film only showed a small peak of TiO 2 at 25.5°, which represented the tetragonal anatase (101) structure of the mesoporous. 32 The diffraction peaks (marked with asterisks) at 26.54, 33.74, 37.8, 51.78, 62.08, and 65.56°were attributed to the FTO substrate. 25 3.6.…”

The Influence of the Thickness of Compact TiO2 Electron Transport Layer on the Performance of Planar CH3NH3PbI3 Perovskite Solar Cells

“…The layer should electrically be as thin as possible to provide fast electron transport and low resistive losses. The titaniumoxide-based ETL is also a crucial investigation area reported in a number of studies [18][19][20][21][22]. The titanium dioxide blocking layer can be deposited by various methods: atomic layer deposition (ALD) [23], magnetron sputtering [24], spray pyrolysis [25], electrochemical deposition [26] and spin coating, where the latter is most commonly used.…”

Enhancement of the photovoltaic performance of perovskite solar cells via sono‐synthesis of Al‐doped TiO 2 as the electron transport layer

“…38,39 However, organic materials as ETL in the structure of PSCs can interact with solvents that are employed in the preparation of perovskites, such as N,N-dimethylformamide, and dimethyl sulfoxide, and lead to the rapid destruction of devices. 40 Various deposition methods such as spin coating, 41 screen printing, 42 spray pyrolysis, 43 pulsed laser deposition, 44 etc., have been reported to produce TiO 2 -based ETL for PSCs. These methods require a high annealing temperature, which is not cost-effective.…”