Use of Anodic TiO2 Nanotube Layers as Mesoporous Scaffolds for Fabricating CH3NH3PbI3 Perovskite-based Solid State Solar Cells

TL;DR

This paper demonstrates that filling anodic TiO2 nanotube layers with CH3NH3PbI3 perovskite enhances the performance of solid-state solar cells by creating conformal, interdigitated structures that serve as efficient light absorbers and charge transport pathways.

Contribution

It introduces a simple spin coating method for complete filling of TiO2 nanotube scaffolds with perovskite, improving solar cell efficiency without the need for hole-transporting materials.

Findings

Complete filling of TiO2 nanotubes with perovskite is crucial for efficiency.

Interdigitated perovskite-TiO2 structures enable effective charge separation.

The scaffold acts as both electron collector and blocking layer.

Abstract

We optimize the deposition of CH3NH3PbI3 perovskite into mesoporous electrodes consisting of anodic TiO2 nanotube layers. By a simple spin coating approach, complete filling of the tube scaffolds is obtained, that leads to interdigitated perovskite structures in conformal contact with the TiO2 tube counterparts. Such assemblies can be used as solid state solar cells in hole-transporting material-free configuration, i.e., the tube scaffold serves as electron collector and blocking layer, while the perovskite acts as visible light absorber and hole transporting material. We show that the complete filling of the tube scaffold with the perovskite is essential to improve the solar cell efficiency.