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Title: Blading Phase–Pure Formamidinium–Alloyed Perovskites for High–Efficiency Solar Cells with Low Photovoltage Deficit and Improved Stability

Abstract

Currently, blade-coated perovskite solar cells (PSCs) with high power conversion efficiencies (PCEs), i.e. greater than 20%, normally employ methylammonium lead tri-iodide with a sub-optimal bandgap. Alloyed perovskites with formamidinium (FA) cation have narrower bandgap and thus enhance device photocurrent. However, FA-alloyed perovskites show low phase stability and high moisture sensitivity. Here, we report that incorporating 0.83 molar percent organic halide salts (OHs) into the perovskite inks enables phase-pure, highly crystalline FA-alloyed perovskites with extraordinary optoelectronic properties. Here, the OH molecules modulate the crystal growth, enhance the phase stability, passivate ionic defects at the surface and/or grain boundaries, and enhance the moisture stability of the perovskite film. We demonstrate a high efficiency of 22.0% under 1 sun illumination for blade-coated PSCs with an open-circuit voltage of 1.18 V, corresponding to a very small voltage deficit of 0.33 V, and significantly improved operational stability with 96% of the initial efficiency retained under one sun illumination for 500 hours.

Authors:
ORCiD logo [1];  [2];  [2];  [2]; ORCiD logo [2]
  1. Univ. of North Carolina, Chapel Hill, NC (United States); Univ. of Queensland, Brisbane, QLD (Australia)
  2. Univ. of North Carolina, Chapel Hill, NC (United States)
Publication Date:
Research Org.:
Univ. of North Carolina, Chapel Hill, NC (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1698277
Grant/Contract Number:  
EE0008749
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Advanced Materials
Additional Journal Information:
Journal Volume: 32; Journal Issue: 28; Journal ID: ISSN 0935-9648
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; perovskite solar cells; light harvesting; charge recombination; passivation; charge collection

Citation Formats

Wu, Wu‐Qiang, Rudd, Peter N., Wang, Qi, Yang, Zhibin, and Huang, Jinsong. Blading Phase–Pure Formamidinium–Alloyed Perovskites for High–Efficiency Solar Cells with Low Photovoltage Deficit and Improved Stability. United States: N. p., 2020. Web. doi:10.1002/adma.202000995.
Wu, Wu‐Qiang, Rudd, Peter N., Wang, Qi, Yang, Zhibin, & Huang, Jinsong. Blading Phase–Pure Formamidinium–Alloyed Perovskites for High–Efficiency Solar Cells with Low Photovoltage Deficit and Improved Stability. United States. https://doi.org/10.1002/adma.202000995
Wu, Wu‐Qiang, Rudd, Peter N., Wang, Qi, Yang, Zhibin, and Huang, Jinsong. Thu . "Blading Phase–Pure Formamidinium–Alloyed Perovskites for High–Efficiency Solar Cells with Low Photovoltage Deficit and Improved Stability". United States. https://doi.org/10.1002/adma.202000995.
@article{osti_1698277,
title = {Blading Phase–Pure Formamidinium–Alloyed Perovskites for High–Efficiency Solar Cells with Low Photovoltage Deficit and Improved Stability},
author = {Wu, Wu‐Qiang and Rudd, Peter N. and Wang, Qi and Yang, Zhibin and Huang, Jinsong},
abstractNote = {Currently, blade-coated perovskite solar cells (PSCs) with high power conversion efficiencies (PCEs), i.e. greater than 20%, normally employ methylammonium lead tri-iodide with a sub-optimal bandgap. Alloyed perovskites with formamidinium (FA) cation have narrower bandgap and thus enhance device photocurrent. However, FA-alloyed perovskites show low phase stability and high moisture sensitivity. Here, we report that incorporating 0.83 molar percent organic halide salts (OHs) into the perovskite inks enables phase-pure, highly crystalline FA-alloyed perovskites with extraordinary optoelectronic properties. Here, the OH molecules modulate the crystal growth, enhance the phase stability, passivate ionic defects at the surface and/or grain boundaries, and enhance the moisture stability of the perovskite film. We demonstrate a high efficiency of 22.0% under 1 sun illumination for blade-coated PSCs with an open-circuit voltage of 1.18 V, corresponding to a very small voltage deficit of 0.33 V, and significantly improved operational stability with 96% of the initial efficiency retained under one sun illumination for 500 hours.},
doi = {10.1002/adma.202000995},
url = {https://www.osti.gov/biblio/1698277}, journal = {Advanced Materials},
issn = {0935-9648},
number = 28,
volume = 32,
place = {United States},
year = {2020},
month = {5}
}

Journal Article:
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Works referenced in this record:

Toward Cost-Effective Solar Energy Use
journal, February 2007


Inkjet‐Printed Micrometer‐Thick Perovskite Solar Cells with Large Columnar Grains
journal, December 2019


Methylammonium-free, high-performance, and stable perovskite solar cells on a planar architecture
journal, October 2018


A fluorene-terminated hole-transporting material for highly efficient and stable perovskite solar cells
journal, July 2018


Iodide management in formamidinium-lead-halide–based perovskite layers for efficient solar cells
journal, June 2017


Compositional engineering of perovskite materials for high-performance solar cells
journal, January 2015


2D perovskite stabilized phase-pure formamidinium perovskite solar cells
journal, August 2018


Composition Engineering in Doctor-Blading of Perovskite Solar Cells
journal, May 2017


Air-Stable, Efficient Mixed-Cation Perovskite Solar Cells with Cu Electrode by Scalable Fabrication of Active Layer
journal, April 2016


Self-formed grain boundary healing layer for highly efficient CH3NH3PbI3 perovskite solar cells
journal, June 2016


Orientation Selection during Heterogeneous Nucleation: Implications for Heterogeneous Catalysis
journal, April 2017


Controlling nucleation, growth, and orientation of metal halide perovskite thin films with rationally selected additives
journal, January 2017


Direct calorimetric verification of thermodynamic instability of lead halide hybrid perovskites
journal, June 2016


Thermal unequilibrium of strained black CsPbI 3 thin films
journal, July 2019


The Effect of Hydrophobicity of Ammonium Salts on Stability of Quasi-2D Perovskite Materials in Moist Condition
journal, April 2018


Enhanced efficacy of defect passivation and charge extraction for efficient perovskite photovoltaics with a small open circuit voltage loss
journal, January 2019


Reducing Surface Halide Deficiency for Efficient and Stable Iodide-Based Perovskite Solar Cells
journal, February 2020


The Rise of Textured Perovskite Morphology: Revolutionizing the Pathway toward High‐Performance Optoelectronic Devices
journal, January 2020


Surface passivation of perovskite film for efficient solar cells
journal, April 2019


Molecular doping enabled scalable blading of efficient hole-transport-layer-free perovskite solar cells
journal, April 2018


Tailoring Passivation Molecular Structures for Extremely Small Open-Circuit Voltage Loss in Perovskite Solar Cells
journal, March 2019


Perovskite seeding growth of formamidinium-lead-iodide-based perovskites for efficient and stable solar cells
journal, April 2018


Theoretical study of time-resolved luminescence in semiconductors. III. Trap states in the band gap
journal, September 2015


Solution-processed solar cells based on environmentally friendly AgBiS2 nanocrystals
journal, June 2016


Highly Efficient and Stable Perovskite Solar Cells Based on Monolithically Grained CH 3 NH 3 PbI 3 Film
journal, December 2016


Approaching the fill factor Shockley–Queisser limit in stable, dopant-free triple cation perovskite solar cells
journal, January 2017


Origin and elimination of photocurrent hysteresis by fullerene passivation in CH3NH3PbI3 planar heterojunction solar cells
journal, December 2014


Efficiency Enhancement of Perovskite Solar Cells through Fast Electron Extraction: The Role of Graphene Quantum Dots
journal, February 2014


Highly efficient planar perovskite solar cells through band alignment engineering
journal, January 2015


High-Performance Fused Ring Electron Acceptor–Perovskite Hybrid
journal, October 2018


Solvent-Mediated Intragranular-Coarsening of CH 3 NH 3 PbI 3 Thin Films toward High-Performance Perovskite Photovoltaics
journal, March 2017


Formamidinium and Cesium Hybridization for Photo- and Moisture-Stable Perovskite Solar Cell
journal, September 2015


Scaling behavior of moisture-induced grain degradation in polycrystalline hybrid perovskite thin films
journal, January 2017


Challenges for commercializing perovskite solar cells
journal, September 2018


Temperature Variation-Induced Performance Decline of Perovskite Solar Cells
journal, April 2018


Trapped charge-driven degradation of perovskite solar cells
journal, November 2016


Unraveling the hidden function of a stabilizer in a precursor in improving hybrid perovskite film morphology for high efficiency solar cells
journal, January 2016