ACS Nano: Induced Crystallization of Perovskites by a Perylene Underlayer for High-Performance Solar Cells

Title:

Induced Crystallization of Perovskites by a Perylene Underlayer for High-Performance Solar Cells

Authors:

Zhao-Kui Wang,^† Xiu Gong,^‡ Meng Li,^† Yun Hu,^† Jin-Miao Wang,^† Heng Ma,^‡and Liangsheng Liao^*,†

Institutions:

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

^‡College of Physics and Electronic Engineering, Henan Normal University, Xinxiang, Henan 453007, China

Abstract:

Perovskite crystallization and interface engineering are regarded as the most crucial factors in achieving high-performance planar heterojunction (PHJ) perovskite solar cells (PSCs). Herein, we demonstrate a thin perylene underlayer via a solution-processable method. By using branch-shaped perylene film as a seed-mediated underlayer, crystalline perovskites with fabric morphology can be formed, which allows for obvious improvement in absorption by a light scattering effect. With its deep highest occupied molecular orbital (HOMO) level, perylene also plays an important role in the energy-level tailoring of poly (3,4-ethylenedioxythiophene): poly(styrenesulphonate) (PEDOT:PSS) and CH₃NH₃PbI_xCl_3-x. In addition, perylene and perovskites form a fully crystalline heterojunction, which is beneficial for minimizing the defect and trap densities. Due to these merits, a maximum power conversion efficiency of 17.06% with improved cell stability is achieved. The finding in this work provides a simple route to control perovskite crystallizaition and to optimize the interfaces in PHJ PSCs simultaneously.

IF:

12.881

Link:

http://pubs.acs.org/doi/abs/10.1021/acsnano.6b01904