Defects of metal-halide perovskites detrimentally influence the optoelectronic properties of the thin film and, ultimately, the photovoltaic performance of perovskite solar cells (PSCs). Especially, defect-mediated nonradiative recombination that occurs at the perovskite interface significantly limits the power conversion efficiency (PCE) of PSCs. In this regard, interfacial engineering or surface treatment of perovskites has become a viable strategy for reducing the density of surface defects, thereby improving the PCE of PSCs. Here, an organic molecule, tris(5-((tetrahydro-2H-pyran-2-yl)oxy)pentyl)phosphine oxide (THPPO), is synthesized and introduced as a defect passivation agent in PSCs. The P≠O terminal group of THPPO, a Lewis base, can passivate perovskite surface defects such as undercoordinated Pb2+. Consequently, improvement of PCEs from 19.87 to 20.70% and from 5.84 to 13.31% are achieved in n-i-p PSCs and hole-transporting layer (HTL)-free PSCs, respectively.
|Number of pages||10|
|Journal||ACS Applied Energy Materials|
|State||Published - Feb 22 2021|
Bibliographical noteFunding Information:
The authors acknowledge the Swiss National Science Foundation (SNSF) funding through the Synergia Grant EPISODE (Grant No. CRSII5_171000). The authors acknowledge funding from the European Commission’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 763977 of the PerTPV project. The authors acknowledge Professor Raffaella Buonsanti for the use of the Fluorolog system. The authors thank Dr. Nakamura and Dr. Koganezawa at the Japan Synchrotron Radiation Research Institute (JASRI). The GIWAXS measurement was performed at SPring-8 at BL19B2 with the approval of the JASRI, Proposal Nos. 2019B1807 and 2019B1808.
© 2021 American Chemical Society.
- Lewis base
- defect passivation
- perovskite solar cells
- phosphine oxide
- surface passivation
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering
- Materials Chemistry