Deepening the Valance Band Edges of NiOx Contacts by Alkaline Earth Metal Doping for Efficient Perovskite Photovoltaics with High Open‐Circuit Voltage. Issue 8 (4th July 2019)

• Record Type: Journal Article
• Authors: Ge, Bing; Qiao, Hong Wei; Lin, Ze Qing; Zhou, Zi Ren; Chen, Ai Ping; Yang, Shuang; Hou, Yu; Yang, Hua Gui
• Is Part Of: Solar RRL. Volume 3:Issue 8(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-07-04
• Subjects: alkaline earth metal -- doping -- nickel oxide -- perovskite -- solar cells; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.201900192
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Organometallic halide perovskite solar cells (PSCs) are rapidly evolving as the promising photovoltaic technologies with high record efficiency over 24%. The inorganic p‐type semiconductor NiO x is extensively used as important hole transport layers for the realization of stable and hysteresis‐free solar cells due to their good electronic properties, facile fabrication, and excellent chemical endurance. However, the critical issues of NiO x films including poor intrinsic conductivity and mismatched band alignment limit further improvement of the device performance. Herein, it is demonstrated that a versatile alkaline earth metal (Mg, Ca, Sr, and Ba) doping strategy can effectively engineer the electronic properties of NiO x contacts in inverted planar PSCs. Alkaline earth metal doping can deepen valence band maximum and enhance the hole conductivity of NiO x films, which better aligns the energy band in solar cells. The champion device based on Sr‐doped NiO x films attains a power conversion efficiency of 19.49% with a high open‐circuit voltage ( V OC ) of 1.14 V for NiO x ‐based CH3 NH3 PbI3 devices. The resulted device shows negligible hysteresis and high stability as well. This finding provides a systematic doping strategy to further improve the performance of inverted planar PSCs. Abstract : A versatile alkaline earth metals doping strategy is utilized to engineer the electronic structure of NiO x contacts for inverted planar perovskite solar cells, which demonstrates a power conversion efficiency of 19.49% with a high open‐circuit voltage of 1.14 V. Enhanced charge extraction and conductivity are responsible for the high‐performance devices.