Surface optimization to eliminate hysteresis for record efficiency planar perovskite solar cells

Dong Yang, Xin Zhou, Ruixia Yang, Zhou Yang, Wei Yu, Xiuli Wang, Can Li, Shengzhong Liu, Robert P H Chang

Research output: Contribution to journalArticle

275 Citations (Scopus)

Abstract

The electron-transport layer (ETL) between the active perovskite material and the cathode plays a critical role in planar perovskite solar cells. Herein, we report a drastically improved solar cell efficiency via surface optimization of the TiO2 ETL using a special ionic-liquid (IL) that shows high optical transparency and superior electron mobility. As a consequence, the efficiency is promoted to as high as 19.62% (the certified efficiency is 19.42%), exceeding the previous highest efficiency recorded for planar CH3NH3PbI3 perovskite solar cells. Surprisingly, the notorious hysteresis is completely eliminated, likely due to the improved ETL quality that has effectively suppressed ion migration in the perovskite layer and charge accumulation at the interfaces, higher electron mobility to balance the hole flux at the anode, and a better growth platform for the high quality perovskite absorber. Both experimental analyses and theoretical calculations reveal that the anion group of the IL bonds to TiO2, leading to a higher electron mobility and a well-matched work function. Meanwhile, the cation group interfaces with adjacent perovskite grains to provide an effective channel for electron transport and a suitable setting to grow low trap-state density perovskite for improved device performance.

Original languageEnglish
Pages (from-to)3071-3078
Number of pages8
JournalEnergy and Environmental Science
Volume9
Issue number10
DOIs
Publication statusPublished - Oct 1 2016

Fingerprint

perovskite
hysteresis
Perovskite
Hysteresis
Electron mobility
electron
Ionic Liquids
Ionic liquids
Transparency
Anions
Cations
Solar cells
Anodes
Cathodes
Negative ions
Positive ions
Perovskite solar cells
solar cell
Ions
Fluxes

ASJC Scopus subject areas

  • Environmental Chemistry
  • Renewable Energy, Sustainability and the Environment
  • Nuclear Energy and Engineering
  • Pollution

Cite this

Surface optimization to eliminate hysteresis for record efficiency planar perovskite solar cells. / Yang, Dong; Zhou, Xin; Yang, Ruixia; Yang, Zhou; Yu, Wei; Wang, Xiuli; Li, Can; Liu, Shengzhong; Chang, Robert P H.

In: Energy and Environmental Science, Vol. 9, No. 10, 01.10.2016, p. 3071-3078.

Research output: Contribution to journalArticle

Yang, Dong ; Zhou, Xin ; Yang, Ruixia ; Yang, Zhou ; Yu, Wei ; Wang, Xiuli ; Li, Can ; Liu, Shengzhong ; Chang, Robert P H. / Surface optimization to eliminate hysteresis for record efficiency planar perovskite solar cells. In: Energy and Environmental Science. 2016 ; Vol. 9, No. 10. pp. 3071-3078.
@article{a2598e4e8f9841c09446719efb73437f,
title = "Surface optimization to eliminate hysteresis for record efficiency planar perovskite solar cells",
abstract = "The electron-transport layer (ETL) between the active perovskite material and the cathode plays a critical role in planar perovskite solar cells. Herein, we report a drastically improved solar cell efficiency via surface optimization of the TiO2 ETL using a special ionic-liquid (IL) that shows high optical transparency and superior electron mobility. As a consequence, the efficiency is promoted to as high as 19.62{\%} (the certified efficiency is 19.42{\%}), exceeding the previous highest efficiency recorded for planar CH3NH3PbI3 perovskite solar cells. Surprisingly, the notorious hysteresis is completely eliminated, likely due to the improved ETL quality that has effectively suppressed ion migration in the perovskite layer and charge accumulation at the interfaces, higher electron mobility to balance the hole flux at the anode, and a better growth platform for the high quality perovskite absorber. Both experimental analyses and theoretical calculations reveal that the anion group of the IL bonds to TiO2, leading to a higher electron mobility and a well-matched work function. Meanwhile, the cation group interfaces with adjacent perovskite grains to provide an effective channel for electron transport and a suitable setting to grow low trap-state density perovskite for improved device performance.",
author = "Dong Yang and Xin Zhou and Ruixia Yang and Zhou Yang and Wei Yu and Xiuli Wang and Can Li and Shengzhong Liu and Chang, {Robert P H}",
year = "2016",
month = "10",
day = "1",
doi = "10.1039/c6ee02139e",
language = "English",
volume = "9",
pages = "3071--3078",
journal = "Energy and Environmental Science",
issn = "1754-5692",
publisher = "Royal Society of Chemistry",
number = "10",

}

TY - JOUR

T1 - Surface optimization to eliminate hysteresis for record efficiency planar perovskite solar cells

AU - Yang, Dong

AU - Zhou, Xin

AU - Yang, Ruixia

AU - Yang, Zhou

AU - Yu, Wei

AU - Wang, Xiuli

AU - Li, Can

AU - Liu, Shengzhong

AU - Chang, Robert P H

PY - 2016/10/1

Y1 - 2016/10/1

N2 - The electron-transport layer (ETL) between the active perovskite material and the cathode plays a critical role in planar perovskite solar cells. Herein, we report a drastically improved solar cell efficiency via surface optimization of the TiO2 ETL using a special ionic-liquid (IL) that shows high optical transparency and superior electron mobility. As a consequence, the efficiency is promoted to as high as 19.62% (the certified efficiency is 19.42%), exceeding the previous highest efficiency recorded for planar CH3NH3PbI3 perovskite solar cells. Surprisingly, the notorious hysteresis is completely eliminated, likely due to the improved ETL quality that has effectively suppressed ion migration in the perovskite layer and charge accumulation at the interfaces, higher electron mobility to balance the hole flux at the anode, and a better growth platform for the high quality perovskite absorber. Both experimental analyses and theoretical calculations reveal that the anion group of the IL bonds to TiO2, leading to a higher electron mobility and a well-matched work function. Meanwhile, the cation group interfaces with adjacent perovskite grains to provide an effective channel for electron transport and a suitable setting to grow low trap-state density perovskite for improved device performance.

AB - The electron-transport layer (ETL) between the active perovskite material and the cathode plays a critical role in planar perovskite solar cells. Herein, we report a drastically improved solar cell efficiency via surface optimization of the TiO2 ETL using a special ionic-liquid (IL) that shows high optical transparency and superior electron mobility. As a consequence, the efficiency is promoted to as high as 19.62% (the certified efficiency is 19.42%), exceeding the previous highest efficiency recorded for planar CH3NH3PbI3 perovskite solar cells. Surprisingly, the notorious hysteresis is completely eliminated, likely due to the improved ETL quality that has effectively suppressed ion migration in the perovskite layer and charge accumulation at the interfaces, higher electron mobility to balance the hole flux at the anode, and a better growth platform for the high quality perovskite absorber. Both experimental analyses and theoretical calculations reveal that the anion group of the IL bonds to TiO2, leading to a higher electron mobility and a well-matched work function. Meanwhile, the cation group interfaces with adjacent perovskite grains to provide an effective channel for electron transport and a suitable setting to grow low trap-state density perovskite for improved device performance.

UR - http://www.scopus.com/inward/record.url?scp=84990935179&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84990935179&partnerID=8YFLogxK

U2 - 10.1039/c6ee02139e

DO - 10.1039/c6ee02139e

M3 - Article

VL - 9

SP - 3071

EP - 3078

JO - Energy and Environmental Science

JF - Energy and Environmental Science

SN - 1754-5692

IS - 10

ER -