Abstract

Organic-inorganic hybrid halide perovskite solar cells (PSCs) have been a trending topic in recent years. Significant progress has been made to increase their power conversion efficiency (PCE) to more than 20%. However, the poor stability of PSCs in both working and non-working conditions results in rapid degradation through multiple environmental erosions such as water, heat, and UV light. Attempts have been made to resolve the rapid-degradation problems, including formula changes, transport layer improvements, and encapsulations, but none of these have effectively resolved the dilemma. This paper reports our findings on adding inorganic films as surface-passivation layers on top of the hybrid perovskite materials, which not only enhance stability by eliminating weak sites but also prevent water penetration by using a water-stable layer. The surface-passivated hybrid perovskite layer indicates a slight increase of bandgap energy (Eg=1.76 eV), compared to the original methylammonium lead iodide (MAPbI3, Eg=1.61 eV) layer, allowing for more stable perovskite layer with a small sacrifice in the photoluminescence property, which represents a lower charge diffusion rate and higher bandgap energy. Our finding offers an alternative approach to resolving the low stability issue for PSC fabrication.

Highlights

  • Organic perovskite material, methylammonium lead iodide (MAPbI3 ), reported by Miyasaka et al [1] in 2009, was first introduced as a dye material in the dye-sensitized solar cell (DSSC) with a mere 3.8% power conversion efficiency (PCE)

  • The PCE has reached over 20% in layer-constructed perovskite solar cells (PSCs), approaching the PCE of 26.7% for single-junction crystalline silicon solar cells [2] by the end of 2017

  • Silicon-based solar cells have higher efficiency and much longer lifetime compared to PSCs, they require a costly industry to support the production of monocrystalline silicon

Read more

Summary

Introduction

Methylammonium lead iodide (MAPbI3 ), reported by Miyasaka et al [1] in 2009, was first introduced as a dye material in the dye-sensitized solar cell (DSSC) with a mere 3.8% power conversion efficiency (PCE). The stability of organic PSCs could be improved by using an all-inorganic perovskite structure, such as cesium lead iodide (CsPbI3 ), the approach would introduce a phase transition at ambient temperature which produces a poor photoluminescence property, reducing the PCE to a lower value [6]. Other attempts to improve the stability include doping with additives [11], adding protective electrode layers [12], encapsulation [13] and replacing ETM (electron transfer materials) and HTM (hole transfer materials) [12,14,15], but all result in limited improvement It is the purpose of this report to improve the stability by focusing on the original structure of perovskites for solar cells.

Materials
Synthesis
Characterization
Discussion
Water-induced
Crystal data of CsPbI
Scanning ElectronFigure
The bottom layer is made of of
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call