Evaluation of the impact of trivalent metal doping on the performance of titanium dioxide as an electron transport layer of Inverted-Structured organic solar cells

Inverted organic solar cells (OSCs) are becoming more popular because to their better durability and photo stability; nonetheless, their power conversion efficiency (PCE) is lower than that of conventional OSCs due to the poor conductivity of the electron transport layer (ETL). Several doped metal oxides have been investigated as possible ETLs to overcome this problem. Various metal doped titanium dioxide (TiO₂) has recently been tested as an ETL for photo- and air- stable OSCs. Due to their physicochemical features, trivalent metals are one of the best possibilities as a TiO₂ doping reagent. Therefore, we investigate at how TiO₂′s performance as an ETL of an inverted OSC may be affected by doping it with a very little quantity of trivalent metal in this study. Additionally, two other metals, such as Indium (In) and Gallium (Ga), are taken into consideration to test the impact of the doping metal's atomic size on TiO₂′s performance as an ETL. The doped-TiO₂ based OSC shows 10.24% higher PCE than undoped-TiO₂ based OSC. Furthermore, despite the fact that Ga's atomic size is substantially smaller than Ti's and In's, both Ga doped-TiO₂ based OSC (7.54%) and In-doped-TiO₂ (7.47%) display almost identical PCE values.