[19p-E101-1~14] 12.5 Organic solar cells

▲ [19p-E101-3] Correlation of surface roughness of TiO₂, grain size of MAPbI₃
and perovskite solar cell performance

〇(D)Methawee Nukunudompanich¹, Kazuma Suzuki¹, Gekko Budiutama¹, Kei Hasegawa¹, Manabu Ihara¹ (1.Tokyo tech.)

Keywords:Perovskite, roughness, grain size

Herein PSCs using spray pyrolysis compact-TiO₂ films as ETL were investigated. The relationship between surface roughness of TiO₂ and MAPbI₃ perovskite grain size distribution has been investigated by using a planar perovskite solar cell. When using condition with lower R_ms of the compact TiO₂ layer, the MAPbI3 grain size tends to larger because of surface smoothness, uniform area for the lower surface nucleation and no crystallization orientation growth barrier from the bottom layer. Therefore, the highly efficient PSC can be achieved by lower R_ms of the TiO₂ compact layer and grain quality of perovskite films with active area 0.54 cm² showed an efficiency of 11.4% with a perovskite grain size about 300 nm. The condition of TiO₂ compact film via spray pyrolysis technique has been optimized to reduce the surface roughness and large TiO₂ as a byproduct on compact TiO₂ layer. However, reproduction from this method for large area devices has set the ultimate challenges because it requires optimization of many parameters.