[18p-F202-1~19] 1.1 Interdisciplinary and General Physics

▲ [18p-F202-19] High-performance Planar Perovskite Solar Cells Exploiting a Compact TiO₂/Anatase TiO₂ Nanoparticles Electron Transport Bilayer

〇(P)Md Shahiduzzaman¹, Hiroto Ashikawa¹, Mizuki Kuniyoshia¹, Tetsuya Kaneko¹, Tetsuhiro Katsumata¹, Tetsuya Taima², Satoru Iwamori¹, Shinjiro Umezu³, Masato Kakihana⁴, Masao Isomura¹, Koji Tomita¹ (1.Tokai Univ., 2.Kanazawa Univ., 3.Waseda Univ., 4.Tohoku Univ.)

Keywords:Planar Perovskite Solar Cells, Interface Engineering, SP-TiO2/SC-Anatase TiO2 NPs Bilayer

Interface engineering plays a promising strategy to produce highly efficient planar heterojunction (PHJ) perovskite solar cells. Higher potential single-crystalline anatase titania nanoparticles (TiO₂ NPs) with average diameter sizes about 6 to 10 nm, were synthesized by a novel one-step hydrothermal route using water-soluble titanium complex as a titanium source. Herein, a novel compact TiO₂/Anatase TiO₂ NPs bilayer was introduced as an electron transport layer (ETL) by comprising spray pyrolysis (SP) deposition and spin-coating (SC) technique, respectively, in PHJ perovskite solar cells. A SP-TiO₂/SC-Anatase TiO₂ NPs bilayer based perovskite solar cells are facilitated more efficient electron transport, charge extraction, and low interfacial recombination, and thus leads champion efficiencies up to 17.05% by a significant decrease of current density versus voltage (J-V) hysteresis, presenting almost 12% enhancement compared to the TiO₂ single layer based counterparts. The PHJ perovskite solar cells exhibited a spectral response that extended from the visible to the near-infrared region with a broad, flat absorption peak of intensity 80%–85% at approximately 380–750 nm. The higher IPCE value of the device with a bilayer in the visible-to-near-infrared wavelength region than those of the other devices suggests that the bilayer layer collect electrons more efficiently at the perovskite/TiO₂ edge because it successfully lowers the interfacial energy barrier. This facial process and significant performance enhancement revealed that the resulted bilayer could be good ETL candidates for high-performance PHJ perovskite solar cells.
Fig. (a) Current density versus voltage (J-V) characteristics and (b) incident photon-to-current conversion efficiency (IPCE) spectra of devices with and without bilayer.
Keywords: Planar Perovskite Solar Cells, Interface Engineering; SP-TiO₂/SC-Anatase TiO₂ NPs Bilayer.
Acknowledgement: This study was supported in part by Research and Study Project of Tokai University General Research Organization.