Enhancement of the hole conducting effect of NiO by a N2 blow drying method in printable perovskite solar cells with low-temperature carbon as the counter electrode

• Published in: Nanoscale 2017-05, Vol.9 (17), p.5475-5482
• Main Authors: Peiris, T. A. Nirmal, Baranwal, Ajay K, Kanda, Hiroyuki, Fukumoto, Shota, Kanaya, Shusaku, Cojocaru, Ludmila, Bessho, Takeru, Miyasaka, Tsutomu, Segawa, Hiroshi, Ito, Seigo
• Format: Article
• Language: English
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c7nr00372b

In this article, we demonstrate for the first time a mesoscopic printable perovskite solar cell (PSC) using NiO as the hole transporting material and low-temperature processed carbon as the counter electrode. A single deposition method assisted by N 2 blow drying was used for the deposition of MAPbI 3 on a TiO 2 /ZrO 2 /NiO screen-printed electrode. As the final step a low-temperature processing ( i.e. 75 °C) carbon counter layer was fabricated on MAPbI 3 by a blade coating method. It is found that the capping layer thickness of MAPbI 3 has a significant effect on the device efficiency, especially when NiO is introduced as a hole transporting material into the structure. Electrochemical impedance spectroscopy demonstrates good charge transport characteristics for the device with a thin MAPbI 3 capping layer obtained by the N 2 blow drying method. Our best performing device demonstrated a remarkable photovoltaic performance with a short-circuit current density ( J sc ) of 22.38 mA cm −2 , an open circuit voltage ( V oc ) of 0.97 V, and a fill factor (FF) of 0.50 corresponding to a photo-conversion efficiency (PCE) of 10.83%. Moreover, the un-encapsulated device exhibited advantageous stability over 1000 h in air in the dark. Our study indicates that the capping layer thickness of MAPbI 3 is highly affecting the hole collecting effect of NiO in mesoscopic PSCs.