Enhancement of the Open-Circuit Voltage and Hole Conduction of Tetraphenyl Porphyrin/C60 Multilayered Photovoltaic Device by the Insertion of Oxide Hole Collection Layers
Year: 2011
Type: article
Abstract: We investigated the photovoltaic properties of organic multilayered photovoltaic devices consisting of Indium–tin-oxide (ITO)/oxide/tetraphenyl porphyrin (H2TPP, ZnTPP)/fullerene (C60)/bathocuproine (BCP)/Al structures. The open-circuit voltage V OC increases with the thickness of porphyrin layers between 10 and 30 nm. The upper limit of V OC is attributed to the built-in potential and the energy difference between the highest occupied molecular orbital (HOMO) of H2TPP and the lowest unoccupied molecular orbital (LUMO) of the C60 layer ΔE. The use of oxide hole collection layers, such as NiO and MoO3, is effective for increasing the built-in potential across the organic layers resulting in the improved V OC. The “kink” in the J–V curve observed at approximately V OC for the device with a thick H2TPP layer and the device with and without a MoO x layer is analyzed on the basis of the Poole–Frenkel and Schottky models assuming the amorphous porphyrin layers as dielectrics. The resistance of the organic layers is dominated by the field-dependent bulk resistance of H2TPP films for V
Authors: Eiji Itoh, Yuji Higuchi, Daisuke Furuhata, Toshiki Shirotori
Institution: Shinshu University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2066623218