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

Title: Identifying barriers to charge-carriers in the bulk and surface regions of Cu2ZnSnS4 nanocrystal films by x-ray absorption fine structures (XAFSs)

Journal Article · · Journal of Chemical Physics
DOI:https://doi.org/10.1063/1.4967863· OSTI ID:1334802
 [1];  [1]; ORCiD logo [1];  [1];  [1]
  1. Univ. of Western Ontario, London, ON (Canada). Dept. of Chemistry and Soochow Univ.-Western, Univ. Centre for Synchrotron Radiation Research

Solar cell performance is most affected by the quality of the light absorber layer. For thin-film devices, this becomes a two-fold problem of maintaining a low-cost design with well-ordered nanocrystal (NC) structure. The use of Cu2ZnSnS4 (CZTS) NCs as the light absorber films forms an ideal low-cost design, but the quaternary structure makes it difficult to maintain a well-ordered layer without the use of high-temperature treatments. There is little understanding of how CZTS NC structures affect the photoconversion efficiency, the charge-carriers, and therefore the performance of the device manufactured from it. To examine these relationships, the measured photoresponse from the photo-generation of charge-carrier electron-hole pairs was compared against the crystal structure, as short-range and long-range crystal orders for the films. The photoresponse simplifies the electronic properties into three basic steps that can be associated with changes in energy levels within the band structure. These changes result in the formation of barriers to charge-carrier flow. In this work, the extent of these barriers was determined using synchrotron-based X-ray absorbance fine structure to probe the individual metal centers in the film, and comparing these to molecular simulations of the ideal extended xray absorbance fine structure scattering. This allowed for the quantification of bond lengths, and thus an interpretation of the distortions in the crystal lattice. The various characteristics of the photoresponse were then correlated to the crystallographic order and used to gain physical insight into barriers to charge-carriers in the bulk and surface regions of CZTS films.

Research Organization:
Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities Division; Natural Sciences and Engineering Research Council of Canada (NSERC)
Grant/Contract Number:
AC02-06CH11357
OSTI ID:
1334802
Journal Information:
Journal of Chemical Physics, Vol. 145, Issue 20; ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
ENGLISH
Citation Metrics:
Cited by: 5 works
Citation information provided by
Web of Science

References (57)

ATHENA , ARTEMIS , HEPHAESTUS : data analysis for X-ray absorption spectroscopy using IFEFFIT journal June 2005
Composition Control and Formation Pathway of CZTS and CZTGS Nanocrystal Inks for Kesterite Solar Cells journal February 2015
Re-evaluating the Cu K pre-edge XAS transition in complexes with covalent metal–ligand interactions journal January 2015
High-Efficiency Solution-Processed Cu 2 ZnSn(S,Se) 4 Thin-Film Solar Cells Prepared from Binary and Ternary Nanoparticles journal September 2012
Theoretical modeling of the complexes of iron impurities and oxygen vacancies in SrTiO 3 journal March 2013
Aliovalent Substitutions in Olivine Lithium Iron Phosphate and Impact on Structure and Properties journal April 2009
Assignment of pre-edge features in the Ru K-edge X-ray absorption spectra of organometallic ruthenium complexes journal March 2008
Effects of Cu content on the photoelectrochemistry of Cu 2 ZnSnS 4 nanocrystal thin films journal April 2015
Defect physics of the kesterite thin-film solar cell absorber Cu2ZnSnS4 journal January 2010
Band alignment at the Cu2ZnSn(SxSe1−x)4/CdS interface journal June 2011
Recent Progress on Synchrotron-Based In-Situ Soft X-ray Spectroscopy for Energy Materials journal May 2014
VESTA 3 for three-dimensional visualization of crystal, volumetric and morphology data journal October 2011
In situ monitoring of electrophoretic deposition of Cu2ZnSnS4 nanocrystals journal January 2013
EXAFS: Basic Principles and Data Analysis book January 1986
Relations between the Concentrations of Imperfections in Crystalline Solids book January 1956
Defect properties of CuInSe2 and CuGaSe2 journal November 2005
Physical Chemistry of Semiconductor−Liquid Interfaces journal January 1996
High-Efficiency Solar Cell with Earth-Abundant Liquid-Processed Absorber journal May 2010
Introductory overview: X-ray absorption spectroscopy and structural genomics journal December 2002
Present and Future of Global Energy Sources journal January 2015
Role of crystal defects in red long-lasting phosphorescence of CaMgSi2O6:Mn diopsides journal January 2012
Abundance of Cu Zn  + Sn Zn and 2Cu Zn  + Sn Zn defect clusters in kesterite solar cells journal November 2012
Dye-Sensitized Nanostructured p-Type Nickel Oxide Film as a Photocathode for a Solar Cell journal October 1999
A High Efficiency Electrodeposited Cu2ZnSnS4 Solar Cell journal November 2011
Muffin-tin potentials in EXAFS analysis journal July 2015
Defect-related lattice strain and the transition temperature in ferroelectric thin films journal September 2004
Beyond 11% Efficiency: Characteristics of State-of-the-Art Cu 2 ZnSn(S,Se) 4 Solar Cells journal August 2012
Cu 2 ZnSnS 4 Thin Films Generated from a Single Solution Based Precursor: The Effect of Na and Sb Doping journal July 2016
Anharmonic Contributions to the Debye-Waller Factor journal March 1963
The path towards a high-performance solution-processed kesterite solar cell journal June 2011
Carbon monoxide oxidation catalysed by defective palladium chloride: DFT calculations, EXAFS, and in situ DRIRS measurements journal January 2016
Controlling Cu2ZnSnS4 photocatalytic ability through alterations in sulfur availability journal February 2016
Enhanced Conversion Efficiencies of Cu 2 ZnSnS 4 -Based Thin Film Solar Cells by Using Preferential Etching Technique journal April 2008
Impact of water-rinse treatment on Cu 2 ZnSnS 4 studied by X-ray absorption near-edge structure analysis : Impact of water-rinse treatment on Cu journal April 2015
One-step synthesis of high quality kesterite Cu 2 ZnSnS 4 nanocrystals – a hydrothermal approach journal January 2014
Microscopic origin of the charge transfer in single crystals based on thiophene derivatives: A combined NEXAFS and density functional theory approach journal July 2016
Cost-Effective Electrophoretic Deposition of Cu 2 ZnSnS 4 Nanocrystals for Photovoltaic Films journal December 2015
Neutron Diffraction and X-ray Absorption Fine Structure Evidence for Local Lattice Distortions and Aperiodic Antisite Substitution in Cu 2 ZnSnS 4 Nanoparticles journal October 2014
Enhanced Conductivity in CZTS/Cu 2– x Se Nanocrystal Thin Films: Growth of a Conductive Shell journal February 2016
Defect-Dominated Doping and Contact Resistance in MoS 2 journal February 2014
Optical designs that improve the efficiency of Cu 2 ZnSn(S,Se) 4 solar cells journal January 2014
Development of CZTS-based thin film solar cells journal February 2009
p ‐type zinc‐blende GaN on GaAs substrates journal August 1993
Kinetics and mechanisms of Zn complexation on metal oxides using EXAFS spectroscopy journal July 2003
Pinning down high-performance Cu-chalcogenides as thin-film solar cell absorbers: A successive screening approach journal May 2016
In Situ X-ray Near-Edge Absorption Spectroscopy Investigation of the State of Charge of All-Vanadium Redox Flow Batteries journal September 2014
Predicted roles of defects on band offsets and energetics at CIGS (Cu(In,Ga)Se 2 /CdS) solar cell interfaces and implications for improving performance journal September 2014
Presence of excited electronic state in CaWO 4 crystals provoked by a tetrahedral distortion: An experimental and theoretical investigation journal August 2011
Determination of secondary phases in kesterite Cu 2 ZnSnS 4 thin films by x-ray absorption near edge structure analysis journal December 2011
Ceramic Materials book January 2013
X-ray-absorption near-edge structure of transition-metal zinc-blende semiconductors: Calculation versus experimental data and the pre-edge feature journal February 1992
Crystal structure and defect reactions in the kesterite solar cell absorber Cu[sub 2]ZnSnS[sub 4] (CZTS): Theoretical insights
  • Walsh, Aron; Chen, Shiyou; Gong, X. G.
  • PHYSICS OF SEMICONDUCTORS: 30th International Conference on the Physics of Semiconductors, AIP Conference Proceedings https://doi.org/10.1063/1.3666258
conference January 2011
Optimization of the Cu2ZnSnS4 nanocrystal recipe by means of photoelectrochemical measurements journal January 2013
Cu2ZnSnS4 (CZTS) nanoparticle based nontoxic and earth-abundant hybrid pn-junction solar cells journal January 2012
Comparative study of the luminescence and intrinsic point defects in the kesterite Cu 2 ZnSnS 4 and chalcopyrite Cu(In,Ga)Se 2 thin films used in photovoltaic applications journal October 2011
Optically induced structural transformation in disordered kesterite Cu2ZnSnS4 journal November 2013
New routes to sustainable photovoltaics: evaluation of Cu 2 ZnSnS 4 as an alternative absorber material journal September 2008

Cited By (1)

Probing the CZTS/CdS heterojunction utilizing photoelectrochemistry and x-ray absorption spectroscopy journal April 2018