Metal-Oxide-Free Methylammonium Lead Iodide Perovskite-Based Solar Cells: the Influence of Organic Charge Transport Layers

• Published in: Advanced energy materials 2014-10, Vol.4 (15), p.np-n/a
• Main Authors: Malinkiewicz, Olga, Roldán-Carmona, Cristina, Soriano, Alejandra, Bandiello, Enrico, Camacho, Luis, Nazeeruddin, Mohammad Khaja, Bolink, Henk J.
• Format: Article
• Language: English
• Subjects: Blocking; charge transport materials; Current density; Devices; Iodides; Lead (metal); methylammonium lead iodide; Perovskites; Photovoltaic cells; photovoltaic devices; Solar cells; Solar energy
• ISSN: 1614-6832; 1614-6840
• DOI: 10.1002/aenm.201400345

Metal‐oxide‐free methylammonium lead iodide perovskite‐based solar cells are prepared using a dual‐source thermal evaporation method. This method leads to high quality reproducible films with large crystal domain sizes allowing for an in depth study of the effect of perovskite film thickness and the nature of the electron and hole blocking layers on the device performance. The power conversion efficiency increases from 4.7% for a device with only an organic electron blocking layer to almost 15% when an organic hole blocking layer is also employed. In addition to the in depth study on small area cells, larger area cells (approx. 1 cm−2) are prepared and exhibit efficiencies in excess of 10%. An efficient thin‐film photovoltaic device based on a hybrid organic‐inorganic perovskite is developed using a simple device architecture (an n‐type oxide that is scaffold‐free) coupled with an easy, room‐ temperature fabrication process using low‐cost materials. The importance of the organic hole and electron blocking layers is demonstrated, including the effect on the current density and open‐circuit voltage.