title: p-Type mesoscopic NiO as an active interfacial layer for carbon counter electrode based perovskite solar cells.
abstract: Replacement of the ZrO2 insulator layer in the state-of-the-art TiO2/ZrO2/carbon structure by mesoscopic p-type NiO particles led to 39% increase of energy conversion efficiency of hole-conductor-free organometallic perovskite heterojunction solar cells with carbon counter electrodes. In these cells, the light absorber, CH3NH3PbI3, formed instantly inside the pores of the entire TiO2/NiO/carbon layer upon sequential deposition of PbI2 and CH3NH3I. Photoluminescence, impedance spectroscopy and transient photovoltage decay measurements have revealed that introduction of NiO extended the electron lifetime and augmented the hole extraction of the counter electrode. As a result, the photocurrent and open-circuit voltage both increased, resulting in a cell with impressive energy conversion efficiency of 11.4% under AM1.5G conditions.
authors.affiliation: Michael Grätzel Center for Mesoscopic Solar Cells, Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China. zhixin-zhao@hust.edu.cn mingkui.wang@mail.hust.edu.cn.
authors.forename: Zonghao
authors.initials: Z
authors.lastname: Liu
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.forename: Xiaobao
authors.initials: X
authors.lastname: Xu
authors.forename: Lingling
authors.initials: L
authors.lastname: Bu
authors.forename: Wenjun
authors.initials: W
authors.lastname: Zhang
authors.forename: Wenhui
authors.initials: W
authors.lastname: Li
authors.forename: Zhixin
authors.initials: Z
authors.lastname: Zhao
authors.forename: Mingkui
authors.initials: M
authors.lastname: Wang
authors.forename: Yi-Bing
authors.initials: YB
authors.lastname: Cheng
authors.forename: Hongshan
authors.initials: H
authors.lastname: He