Toward Highly Thermal Stable Perovskite Solar Cells by Rational Design of Interfacial Layer.

Weitao Yang,Hongzheng Chen,Shaoxing Qu,Minmin Shi,Danming Zhong

doi:10.1016/j.isci.2019.11.007

Abstract

SummaryHeat is crucial to the long-term stability of perovskite solar cells (PVSCs). Herein, thermal stability of PVSCs based on metal oxide (MO) and polymer (P) was investigated. Firstly, chemical decomposition behavior of perovskite films was characterized and analyzed, revealing that chemically active MO would accelerate the decomposition of methylamine lead iodide (MAPbI3). Secondly, thermal-induced stress, resulting from the mismatched thermal expansion coefficients of different layers of PVSCs, and its effect on the mechanical stability of perovskite films were studied. Combining experiment and simulation, we conclude that “soft” (low modulus) and thick (>20 nm) interfacial layers offer better relaxation of thermal-induced stress. As a result, PVSCs employing thick polymer interfacial layer offer a remarkably improved thermal stability. This work offers not only the degradation insight of perovskite films on different substrates but also the path toward highly thermal stable PVSCs by rational design of interfacial layers.

Highlights

Perovskite solar cells (PVSCs) based on halide lead perovskite such as methylamine lead iodide (MAPbI3) have emerged as one of the most promising candidates for solar energy harvest due to their outstanding photo-electronic properties and compatibility to large-area solution-processing fabrication
Decomposition of MAPbI3 under Thermal Aging indium tin oxide (ITO) glass substrates coated with four different interfacial layers of compact tin oxides (SnO2), compact titanium oxides (TiO2), poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS Al 4083), and poly[bis(4-phenyl) (2,4,6-trimethylphenyl)amine] (PTAA) were prepared according to the previous reports (Huang et al, 2016; Liu et al, 2018; Yang et al, 2019; Zhou et al, 2014)
PVSCs based on SnO2 (30 nm), PTAA (7 nm), and PEDOT:PSS/PTAA (21 nm) interfacial layers were fabricated, and their thermal stability were examined by placing different devices on 100C hotplate in glove box

Summary

SUMMARY

Heat is crucial to the long-term stability of perovskite solar cells (PVSCs). Thermal stability of PVSCs based on metal oxide (MO) and polymer (P) was investigated. Chemical decomposition behavior of perovskite films was characterized and analyzed, revealing that chemically active MO would accelerate the decomposition of methylamine lead iodide (MAPbI3). Thermal-induced stress, resulting from the mismatched thermal expansion coefficients of different layers of PVSCs, and its effect on the mechanical stability of perovskite films were studied. We conclude that ‘‘soft’’ (low modulus) and thick (>20 nm) interfacial layers offer better relaxation of thermal-induced stress. PVSCs employing thick polymer interfacial layer offer a remarkably improved thermal stability. This work offers the degradation insight of perovskite films on different substrates and the path toward highly thermal stable PVSCs by rational design of interfacial layers

INTRODUCTION

RESULTS AND DISCUSSION

F PTAA-based TA

Conclusion