skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Cu 2ZnSnS 4 solar cells with over 10% power conversion efficiency enabled by heterojunction heat treatment

Abstract

Sulfide kesterite Cu 2ZnSnS 4 provides an attractive low-cost, environmentally benign and stable photovoltaic material, yet the record power conversion efficiency for such solar cells has been stagnant at around 9% for years. Severe non-radiative recombination within the heterojunction region is a major cause limiting voltage output and overall performance. Here we report a certified 11% efficiency Cu 2ZnSnS 4 solar cell with a high 730 mV open-circuit voltage using heat treatment to reduce heterojunction recombination. This heat treatment facilitates elemental inter-diffusion, directly inducing Cd atoms to occupy Zn or Cu lattice sites, and promotes Na accumulation accompanied by local Cu deficiency within the heterojunction region. Consequently, new phases are formed near the hetero-interface and more favourable conduction band alignment is obtained, contributing to reduced non-radiative recombination. Using this approach, we also demonstrate a certified centimetre-scale (1.11 cm2) 10% efficiency Cu 2ZnSnS 4 photovoltaic device; the first kesterite cell (including selenium-containing) of standard centimetre-size to exceed 10%.

Authors:
 [1]; ORCiD logo [1]; ORCiD logo [1];  [2];  [1];  [1];  [1];  [1];  [1];  [3];  [3];  [3];  [1];  [1];  [1]; ORCiD logo [4];  [1]; ORCiD logo [1]
  1. Univ. of New South Wales, Sydney, NSW (Australia)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. Univ. of Sydney, NSW (Australia)
  4. East China Normal Univ. (ECNU), Shanghai (China)
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1466563
Report Number(s):
NREL/JA-5K00-72245
Journal ID: ISSN 2058-7546
Grant/Contract Number:  
AC36-08GO28308
Resource Type:
Accepted Manuscript
Journal Name:
Nature Energy
Additional Journal Information:
Journal Volume: 3; Journal Issue: 9; Journal ID: ISSN 2058-7546
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; conversion efficiency; copper; copper compounds; efficiency; energy efficiency; heat treatment; heterojunctions; open circuit voltage; solar cells; solar power generation; tin compounds zinc compounds

Citation Formats

Yan, Chang, Huang, Jialiang, Sun, Kaiwen, Johnston, Steve, Zhang, Yuanfang, Sun, Heng, Pu, Aobo, He, Mingrui, Liu, Fangyang, Eder, Katja, Yang, Limei, Cairney, Julie M., Ekins-Daukes, N. J., Hameiri, Ziv, Stride, John A., Chen, Shiyou, Green, Martin A., and Hao, Xiaojing. Cu2ZnSnS4 solar cells with over 10% power conversion efficiency enabled by heterojunction heat treatment. United States: N. p., 2018. Web. doi:10.1038/s41560-018-0206-0.
Yan, Chang, Huang, Jialiang, Sun, Kaiwen, Johnston, Steve, Zhang, Yuanfang, Sun, Heng, Pu, Aobo, He, Mingrui, Liu, Fangyang, Eder, Katja, Yang, Limei, Cairney, Julie M., Ekins-Daukes, N. J., Hameiri, Ziv, Stride, John A., Chen, Shiyou, Green, Martin A., & Hao, Xiaojing. Cu2ZnSnS4 solar cells with over 10% power conversion efficiency enabled by heterojunction heat treatment. United States. doi:10.1038/s41560-018-0206-0.
Yan, Chang, Huang, Jialiang, Sun, Kaiwen, Johnston, Steve, Zhang, Yuanfang, Sun, Heng, Pu, Aobo, He, Mingrui, Liu, Fangyang, Eder, Katja, Yang, Limei, Cairney, Julie M., Ekins-Daukes, N. J., Hameiri, Ziv, Stride, John A., Chen, Shiyou, Green, Martin A., and Hao, Xiaojing. Mon . "Cu2ZnSnS4 solar cells with over 10% power conversion efficiency enabled by heterojunction heat treatment". United States. doi:10.1038/s41560-018-0206-0. https://www.osti.gov/servlets/purl/1466563.
@article{osti_1466563,
title = {Cu2ZnSnS4 solar cells with over 10% power conversion efficiency enabled by heterojunction heat treatment},
author = {Yan, Chang and Huang, Jialiang and Sun, Kaiwen and Johnston, Steve and Zhang, Yuanfang and Sun, Heng and Pu, Aobo and He, Mingrui and Liu, Fangyang and Eder, Katja and Yang, Limei and Cairney, Julie M. and Ekins-Daukes, N. J. and Hameiri, Ziv and Stride, John A. and Chen, Shiyou and Green, Martin A. and Hao, Xiaojing},
abstractNote = {Sulfide kesterite Cu2ZnSnS4 provides an attractive low-cost, environmentally benign and stable photovoltaic material, yet the record power conversion efficiency for such solar cells has been stagnant at around 9% for years. Severe non-radiative recombination within the heterojunction region is a major cause limiting voltage output and overall performance. Here we report a certified 11% efficiency Cu2ZnSnS4 solar cell with a high 730 mV open-circuit voltage using heat treatment to reduce heterojunction recombination. This heat treatment facilitates elemental inter-diffusion, directly inducing Cd atoms to occupy Zn or Cu lattice sites, and promotes Na accumulation accompanied by local Cu deficiency within the heterojunction region. Consequently, new phases are formed near the hetero-interface and more favourable conduction band alignment is obtained, contributing to reduced non-radiative recombination. Using this approach, we also demonstrate a certified centimetre-scale (1.11 cm2) 10% efficiency Cu2ZnSnS4 photovoltaic device; the first kesterite cell (including selenium-containing) of standard centimetre-size to exceed 10%.},
doi = {10.1038/s41560-018-0206-0},
journal = {Nature Energy},
number = 9,
volume = 3,
place = {United States},
year = {2018},
month = {7}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 113 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Valence band offset at the CdS/Cu 2 ZnSnS 4 interface probed by x-ray photoelectron spectroscopy
journal, April 2013


Impact of Na Dynamics at the Cu 2 ZnSn(S,Se) 4 /CdS Interface During Post Low Temperature Treatment of Absorbers
journal, February 2016

  • Xie, Haibing; López-Marino, Simon; Olar, Tetiana
  • ACS Applied Materials & Interfaces, Vol. 8, Issue 7
  • DOI: 10.1021/acsami.5b12243

Thin film solar cell with 8.4% power conversion efficiency using an earth-abundant Cu 2 ZnSnS 4 absorber : Cu
journal, November 2011

  • Shin, Byungha; Gunawan, Oki; Zhu, Yu
  • Progress in Photovoltaics: Research and Applications, Vol. 21, Issue 1
  • DOI: 10.1002/pip.1174

Incoherent imaging using dynamically scattered coherent electrons
journal, June 1999


Theoretical analysis of the effect of conduction band offset of window/CIS layers on performance of CIS solar cells using device simulation
journal, March 2001

  • Minemoto, Takashi; Matsui, Takuya; Takakura, Hideyuki
  • Solar Energy Materials and Solar Cells, Vol. 67, Issue 1-4
  • DOI: 10.1016/S0927-0248(00)00266-X

Why are kesterite solar cells not 20% efficient?
journal, May 2013


Effects of Back Contact Instability on Cu 2 ZnSnS 4 Devices and Processes
journal, July 2013

  • Scragg, Jonathan J.; Kubart, Tomas; Wätjen, J. Timo
  • Chemistry of Materials, Vol. 25, Issue 15
  • DOI: 10.1021/cm4015223

Zinc-Tin-Oxide Buffer Layer and Low Temperature Post Annealing Resulting in a 9.0% Efficient Cd-Free Cu 2 ZnSnS 4 Solar Cell
journal, April 2017


Commercial progress and challenges for photovoltaics
journal, January 2016


Novel five-state latch using double-peak negative differential resistance and standard ternary inverter
journal, March 2016

  • Shin, Sunhae; Kim, Kyung Rok
  • Japanese Journal of Applied Physics, Vol. 55, Issue 4S
  • DOI: 10.7567/JJAP.55.04ED10

Impact of annealing treatment before buffer layer deposition on Cu 2 ZnSn(S,Se) 4 solar cells
journal, May 2015


Photovoltaic materials: Present efficiencies and future challenges
journal, April 2016


What is the band alignment of Cu 2 ZnSn(S,Se) 4 solar cells?
journal, September 2017


Reduced interface recombination in Cu 2 ZnSnS 4 solar cells with atomic layer deposition Zn 1− x Sn x O y buffer layers
journal, December 2015

  • Platzer-Björkman, C.; Frisk, C.; Larsen, J. K.
  • Applied Physics Letters, Vol. 107, Issue 24
  • DOI: 10.1063/1.4937998

Rear Surface Optimization of CZTS Solar Cells by Use of a Passivation Layer With Nanosized Point Openings
journal, January 2016


Fine-Tuning the Sn Content in CZTSSe Thin Films to Achieve 10.8% Solar Cell Efficiency from Spray-Deposited Water-Ethanol-Based Colloidal Inks
journal, October 2015

  • Larramona, Gerardo; Levcenko, Sergiu; Bourdais, Stéphane
  • Advanced Energy Materials, Vol. 5, Issue 24
  • DOI: 10.1002/aenm.201501404

Nanoscale Microstructure and Chemistry of Cu 2 ZnSnS 4 /CdS Interface in Kesterite Cu 2 ZnSnS 4 Solar Cells
journal, June 2016

  • Liu, Fangyang; Yan, Chang; Huang, Jialiang
  • Advanced Energy Materials, Vol. 6, Issue 15
  • DOI: 10.1002/aenm.201600706

Optimization of post-deposition annealing in Cu 2 ZnSnS 4 thin film solar cells and its impact on device performance
journal, October 2017


High efficiency thin-film CuIn1−xGaxSe2 photovoltaic cells using a Cd1−xZnxS buffer layer
journal, December 2006

  • Bhattacharya, R. N.; Contreras, M. A.; Egaas, B.
  • Applied Physics Letters, Vol. 89, Issue 25
  • DOI: 10.1063/1.2410230

Atom-probe tomographic study of interfaces of Cu 2 ZnSnS 4 photovoltaic cells
journal, September 2014

  • Tajima, S.; Asahi, R.; Isheim, D.
  • Applied Physics Letters, Vol. 105, Issue 9
  • DOI: 10.1063/1.4894858

Structure and Composition of Zn x Cd 1– x S Films Synthesized through Chemical Bath Deposition
journal, June 2012

  • Tosun, B. Selin; Pettit, Chelsea; Campbell, Stephen A.
  • ACS Applied Materials & Interfaces, Vol. 4, Issue 7
  • DOI: 10.1021/am300771k

Engineering Solar Cell Absorbers by Exploring the Band Alignment and Defect Disparity: The Case of Cu- and Ag-Based Kesterite Compounds
journal, October 2015

  • Yuan, Zhen-Kun; Chen, Shiyou; Xiang, Hongjun
  • Advanced Functional Materials, Vol. 25, Issue 43
  • DOI: 10.1002/adfm.201502272

Potassium-induced surface modification of Cu(In,Ga)Se2 thin films for high-efficiency solar cells
journal, November 2013

  • Chirilă, Adrian; Reinhard, Patrick; Pianezzi, Fabian
  • Nature Materials, Vol. 12, Issue 12
  • DOI: 10.1038/nmat3789

Sodium Passivation of the Grain Boundaries in CuInSe 2 and Cu 2 ZnSnS 4 for High-Efficiency Solar Cells
journal, December 2016

  • Liu, Cheng-Yan; Li, Zhi-Ming; Gu, Hong-Yang
  • Advanced Energy Materials, Vol. 7, Issue 8
  • DOI: 10.1002/aenm.201601457

Effects of heavy alkali elements in Cu(In,Ga)Se 2 solar cells with efficiencies up to 22.6%
journal, July 2016

  • Jackson, Philip; Wuerz, Roland; Hariskos, Dimitrios
  • physica status solidi (RRL) - Rapid Research Letters, Vol. 10, Issue 8
  • DOI: 10.1002/pssr.201600199

Solar cell efficiency tables (version 49): Solar cell efficiency tables (version 49)
journal, November 2016

  • Green, Martin A.; Emery, Keith; Hishikawa, Yoshihiro
  • Progress in Photovoltaics: Research and Applications, Vol. 25, Issue 1
  • DOI: 10.1002/pip.2855

New World-Record Efficiency for Pure-Sulfide Cu(In,Ga)S 2 Thin-Film Solar Cell With Cd-Free Buffer Layer via KCN-Free Process
journal, May 2016


Over 9% Efficient Kesterite Cu 2 ZnSnS 4 Solar Cell Fabricated by Using Zn 1- x Cd x S Buffer Layer
journal, April 2016

  • Sun, Kaiwen; Yan, Chang; Liu, Fangyang
  • Advanced Energy Materials, Vol. 6, Issue 12
  • DOI: 10.1002/aenm.201600046

Ultrafast electron transfer in the nanocomposite of the graphene oxide–Au nanocluster with graphene oxide as a donor
journal, January 2014

  • Wen, Xiaoming; Yu, Pyng; Toh, Yon-Rui
  • J. Mater. Chem. C, Vol. 2, Issue 19
  • DOI: 10.1039/C3TC32376E

Defect Engineering in Multinary Earth-Abundant Chalcogenide Photovoltaic Materials
journal, January 2017

  • Shin, Donghyeop; Saparov, Bayrammurad; Mitzi, David B.
  • Advanced Energy Materials, Vol. 7, Issue 11
  • DOI: 10.1002/aenm.201602366

Effects of sodium incorporation in Co-evaporated Cu 2 ZnSnSe 4 thin-film solar cells
journal, April 2013

  • Li, Jian V.; Kuciauskas, Darius; Young, Matthew R.
  • Applied Physics Letters, Vol. 102, Issue 16
  • DOI: 10.1063/1.4802972

Cation Substitution of Solution-Processed Cu 2 ZnSnS 4 Thin Film Solar Cell with over 9% Efficiency
journal, July 2015

  • Su, Zhenghua; Tan, Joel Ming Rui; Li, Xianglin
  • Advanced Energy Materials, Vol. 5, Issue 19
  • DOI: 10.1002/aenm.201500682

Efficient kesterite solar cells with high open-circuit voltage for applications in powering distributed devices
journal, November 2017


Solar cell efficiency tables (version 51)
journal, December 2017

  • Green, Martin A.; Hishikawa, Yoshihiro; Dunlop, Ewan D.
  • Progress in Photovoltaics: Research and Applications, Vol. 26, Issue 1
  • DOI: 10.1002/pip.2978

Cu 2 ZnSnS 4 photovoltaic cell with improved efficiency fabricated by high-temperature annealing after CdS buffer-layer deposition : Cu
journal, October 2016

  • Tajima, Shin; Umehara, Mitsutaro; Hasegawa, Masaki
  • Progress in Photovoltaics: Research and Applications, Vol. 25, Issue 1
  • DOI: 10.1002/pip.2837

Band tailing and efficiency limitation in kesterite solar cells
journal, September 2013

  • Gokmen, Tayfun; Gunawan, Oki; Todorov, Teodor K.
  • Applied Physics Letters, Vol. 103, Issue 10
  • DOI: 10.1063/1.4820250

Classification of Lattice Defects in the Kesterite Cu 2 ZnSnS 4 and Cu 2 ZnSnSe 4 Earth-Abundant Solar Cell Absorbers
journal, February 2013


Beyond 11% Efficiency: Characteristics of State-of-the-Art Cu 2 ZnSn(S,Se) 4 Solar Cells
journal, August 2012

  • Todorov, Teodor K.; Tang, Jiang; Bag, Santanu
  • Advanced Energy Materials, Vol. 3, Issue 1
  • DOI: 10.1002/aenm.201200348

The Consequences of Kesterite Equilibria for Efficient Solar Cells
journal, March 2011

  • Redinger, Alex; Berg, Dominik M.; Dale, Phillip J.
  • Journal of the American Chemical Society, Vol. 133, Issue 10
  • DOI: 10.1021/ja111713g

Interfacial energy level alignments between low-band-gap polymer PTB7 and indium zinc oxide anode
journal, August 2015

  • Shin, Dongguen; Lee, Jeihyun; Park, Soohyung
  • Applied Physics Express, Vol. 8, Issue 9
  • DOI: 10.7567/APEX.8.095701

The path towards a high-performance solution-processed kesterite solar cell
journal, June 2011

  • Mitzi, David B.; Gunawan, Oki; Todorov, Teodor K.
  • Solar Energy Materials and Solar Cells, Vol. 95, Issue 6, p. 1421-1436
  • DOI: 10.1016/j.solmat.2010.11.028

Carrier Generation and Recombination in P-N Junctions and P-N Junction Characteristics
journal, September 1957


Beyond 8% ultrathin kesterite Cu2ZnSnS4 solar cells by interface reaction route controlling and self-organized nanopattern at the back contact
journal, July 2017

  • Liu, Fangyang; Huang, Jialiang; Sun, Kaiwen
  • NPG Asia Materials, Vol. 9, Issue 7
  • DOI: 10.1038/am.2017.103

Device characteristics of high performance Cu2ZnSnS4 solar cell
conference, June 2012

  • Gunawan, Oki; Gokmen, Tayfun; Shin, Byungha S.
  • 2012 IEEE 38th Photovoltaic Specialists Conference (PVSC), 2012 38th IEEE Photovoltaic Specialists Conference
  • DOI: 10.1109/PVSC.2012.6318215

Modelling the effects of distributed series resistance on Suns-Voc, m-Voc and Jsc-Suns curves of solar cells
conference, June 2009

  • Kunz, O.; Varlamov, S.; Aberle, A. G.
  • 2009 34th IEEE Photovoltaic Specialists Conference (PVSC)
  • DOI: 10.1109/PVSC.2009.5411707

    Works referencing / citing this record:

    Enhanced Electrical Conductivity of Sb 2 S 3 Thin Film via C 60 Modification and Improvement in Solar Cell Efficiency
    journal, February 2019


    Flexible Cu2ZnSn(S,Se)4 solar cells with over 10% efficiency and methods of enlarging the cell area
    journal, July 2019


    Effect of Sb and Na Incorporation in Cu 2 ZnSnS 4 Solar Cells
    journal, April 2019

    • Suzon, Md Abdul Aziz; Grenet, Louis; Emieux, Fabrice
    • physica status solidi (a), Vol. 216, Issue 11
    • DOI: 10.1002/pssa.201900070

    Enhanced Electrical Conductivity of Sb 2 S 3 Thin Film via C 60 Modification and Improvement in Solar Cell Efficiency
    journal, February 2019


    Effect of Sb and Na Incorporation in Cu 2 ZnSnS 4 Solar Cells
    journal, April 2019

    • Suzon, Md Abdul Aziz; Grenet, Louis; Emieux, Fabrice
    • physica status solidi (a), Vol. 216, Issue 11
    • DOI: 10.1002/pssa.201900070

    Flexible Cu2ZnSn(S,Se)4 solar cells with over 10% efficiency and methods of enlarging the cell area
    journal, July 2019