Three-dimensional self-branching anatase TiO2 nanorods with the improved carrier collection for SrTiO3-based perovskite solar cells

The organic-inorganic perovskite solar cells based on ternary oxide SrTiO3 shows a higher Voc, attributed to its slightly higher conduction band edge and better morphology of absorber material. However, its less efficient carrier collection and limited overall interfacial areas between the absorber material and the electron-transport layer (ETL), dramatically reducing the Jsc. Here, By adjusting the concentrations of the Ti(OBu)(4), we successfully prepared the three-dimensional (3D) self-branching anatase TiO2 nanorod/SrTiO3 nanocomposites, and slightly tuned the particle size of SrTiO3. With the incorporation of the three-dimensional (3D) self-branching anatase TiO2 nanorod, the Jsc of the device based on SrTiO3 was highly boosted. The best performing solar cell we obtained exhibited a PCE of 9.99% with a Jsc of 19.48 mA/cm(2). The excellent performance could be ascribed to the improvement of charge carrier collection of SrTiO3, better surface coverage and crystallinity of CH3NH3PbI3, and enhanced light scattering ability caused by 3D self-branching anatase TiO2 nanorods. (C) 2016 Elsevier B.V. All rights reserved.