Effects of Niobium Addition into TiO2 Layers on CH3NH3PbI3-based Photovoltaic Devices

Abstract

TiO2/CH3NH3PbI3-based photovoltaic devices were fabricated by a spin-coating method using a mixture solution of niobium(V) ethoxide, and the effects of niobium (Nb) addition to TiO2 layers were investigated. The lattice distance and energy gap of the TiO2 were almost same after Nb addition. The elemental mapping and sheet resistance measurements indicated a wide distribution of Nb and Ti, and a decrease in sheet resistance by Nb addition. The external quantum efficiency and internal quantum efficiency increased by Nb addition to compact TiO2 and mesoporous TiO2 layers, which resulted in an increase in the current density and conversion efficiency of the cell.

Doping of TiO2for sensitized solar cells

“…243 Nb-doping resulted in improved electron injection and transport, resulting in higher J SC . 244,245 In the case of Y-doping a small negative shift of V FB was observed and recombination is slightly reduced. The main reason for the improvement in device performance was increased perovskite loading, leading to a marked increase in J SC .…”

Fabrication and Characterization of a Perovskite-Type Solar Cell with a Substrate Size of 70 mm

“…Except for the mesoporous TiO2 layer [16], the details of the fabrication process are described in previously reported work [8,17,18]. The cell performance depends on the TiO2 layers and perovskite layers to some extent [19][20][21]. The photovoltaic cells were fabricated by the following process.…”

Fabrication and Characterization of Element-Doped Perovskite Solar Cells

“…The electron-transport layers (ETLs) such as TiO 2 are also important for the CH 3 NH 3 PbI 3 -based photovoltaic devices. Here, niobium (V) ethoxide was chosen as an additional chemical for TiO 2 [41]. When niobium (Nb) atoms with five valence electrons are introduced at Ti sites with four valence electrons, extra electrons are introduced in the 3d band and could work as a donor.…”