Paper Title
Combined Configuration of ZnO and TiO2 for Perovskite Solar Cells Application

Abstract
In this research, the use of both zinc oxide (ZnO) and titanium dioxide (TiO2) were reported and compared for perovskite solar cell (PSC) application. ZnO and TiO2 possess similar energy bandgap at about 3.2 eV with TiO2 having slightly wider bandgap compared to ZnO. The deposition method for the ZnO nanorods (NRs) was done by using 2-step method of seed layer deposition by spin coating and followed by NRs’ growth through chemical bath deposition (CBD) method. Meanwhile, compact TiO2 layer was deposited through spin coating method only. For comparison purpose, two configurations of both ZnO and TiO2 materials were used for PSC application with ZnO-TiO2 (ZnO was grown first and followed with compact TiO2 deposition) and TiO2-ZnO (compact TiO2 was spin coated first and ZnO NRs was grown through CBD without seed layer spin coating). The perovskite was deposited through 1-step method and followed with PSC fabrication. Electrical measurement on sunny day revealed that TiO2-ZnO PSC generated higher electrical current and voltage compared to ZnO-TiO2 PSC. Index Terms - Chemical bath deposition, perovskite, TiO2, ZnO