题目：

Composition Stoichiometry of Cs₂AgBiBr₆ Films for Highly Efficient Lead-Free Perovskite Solar Cells

作者：

Femi Igbari,^†,§ Rui Wang,^‡,§ Zhao-Kui Wang,*^,† Xing-Juan Ma,^† Qiang Wang,^† Kai-Li Wang,^† Yue Zhang,^† Liang-Sheng Liao,*^,† and Yang Yang*^,‡

单位：

^†Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft  Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, China

^‡Department of  Materials Science and Engineering, University of California, Los Angeles, California 90095, United States

摘要：

Addressing the toxicity issue in lead-based perovskite compounds by seeking other nontoxic candidate elements represents a promising direction to fabricate lead-free perovskite solar cells. Recently, Cs₂AgBiBr₆ double perovskite achieved by replacing two Pb²⁺ with Ag⁺ and Bi³⁺ in the crystal lattice has drawn much attention owing to the convenient substitution of its chemical compositions. Herein, the dependence of the optoelectronic properties and corresponding photovoltaic performance of Cs₂AgBiBr₆ thin films on the deposition methods of vacuum sublimation and solution processing is investigated. Compared to the vacuum sublimation based one, the solution-processed Cs₂AgBiBr₆ shows inherently higher crystallinity, narrower electronic bandgap, longer photoexcitationlifetime, and higher mobility. The excellent optoelectroni properties are attributed to the accurate composition stoichiometry of Cs₂AgBiBr₆ films based on solution processing. These merits enable the corresponding perovskite solar cells to deliver a champion power conversion efficiency (PCE) of 2.51%, which is the highest PCE in the Cs₂AgBiBr₆-based double perovskite solar cells to date. The finding in this work provides a clear clue that a precise composition stoichiometry could guarantee the formation of high quality multicomponent perovskite films.

影响因子：

12.080

分区情况：

一区

链接：

https://pubs.acs.org/doi/10.1021/acs.nanolett.9b00238

责任编辑：向丹婷