Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS Imaging
Organic photovoltaic materials have recently seen intense interest from the research community. Improvements in device performance are occurring at an impressive rate; however, visualization of the active layer phase separation still remains a challenge. This paper outlines the application of two el...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2015-11-01
|
| Series: | Polymers |
| Subjects: | |
| Online Access: | http://www.mdpi.com/2073-4360/7/11/1523 |
| _version_ | 1811318747563032576 |
|---|---|
| author | Ondrej Dyck Sheng Hu Sanjib Das Jong Keum Kai Xiao Bamin Khomami Gerd Duscher |
| author_facet | Ondrej Dyck Sheng Hu Sanjib Das Jong Keum Kai Xiao Bamin Khomami Gerd Duscher |
| author_sort | Ondrej Dyck |
| collection | DOAJ |
| description | Organic photovoltaic materials have recently seen intense interest from the research community. Improvements in device performance are occurring at an impressive rate; however, visualization of the active layer phase separation still remains a challenge. This paper outlines the application of two electron energy-loss spectroscopic (EELS) imaging techniques that can complement and enhance current phase detection techniques. Specifically, the bulk plasmon peak position, often used to produce contrast between phases in energy filtered transmission electron microscopy (EFTEM), is quantitatively mapped across a sample cross section. A complementary spectrum image capturing the carbon and sulfur core loss edges is compared with the plasmon peak map and found to agree quite well, indicating that carbon and sulfur density differences between the two phases also allows phase discrimination. Additionally, an analytical technique for determining absolute atomic areal density is used to produce an absolute carbon and sulfur areal density map. We show how these maps may be re-interpreted as a phase ratio map, giving quantitative information about the purity of the phases within the junction. |
| first_indexed | 2024-04-13T12:30:56Z |
| format | Article |
| id | doaj.art-c25f47f4edc442689d2564b22bc5414b |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-04-13T12:30:56Z |
| publishDate | 2015-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-c25f47f4edc442689d2564b22bc5414b2022-12-22T02:46:50ZengMDPI AGPolymers2073-43602015-11-017112446246010.3390/polym7111523polym7111523Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS ImagingOndrej Dyck0Sheng Hu1Sanjib Das2Jong Keum3Kai Xiao4Bamin Khomami5Gerd Duscher6Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Knoxville, TN 37996, USADepartment of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Knoxville, TN 37996, USADepartment of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, Knoxville, TN 37996, USACenter for Nanophase Materials Sciences/Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USACenter for Nanophase Materials Sciences/Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USADepartment of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Knoxville, TN 37996, USADepartment of Materials Science and Engineering, University of Tennessee, Knoxville, Knoxville, TN 37996, USAOrganic photovoltaic materials have recently seen intense interest from the research community. Improvements in device performance are occurring at an impressive rate; however, visualization of the active layer phase separation still remains a challenge. This paper outlines the application of two electron energy-loss spectroscopic (EELS) imaging techniques that can complement and enhance current phase detection techniques. Specifically, the bulk plasmon peak position, often used to produce contrast between phases in energy filtered transmission electron microscopy (EFTEM), is quantitatively mapped across a sample cross section. A complementary spectrum image capturing the carbon and sulfur core loss edges is compared with the plasmon peak map and found to agree quite well, indicating that carbon and sulfur density differences between the two phases also allows phase discrimination. Additionally, an analytical technique for determining absolute atomic areal density is used to produce an absolute carbon and sulfur areal density map. We show how these maps may be re-interpreted as a phase ratio map, giving quantitative information about the purity of the phases within the junction.http://www.mdpi.com/2073-4360/7/11/1523phase detectionorganic photovoltaicsplasmon energy mappingelectron energy loss spectroscopyEELS Core-loss mappingEFTEM |
| spellingShingle | Ondrej Dyck Sheng Hu Sanjib Das Jong Keum Kai Xiao Bamin Khomami Gerd Duscher Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS Imaging Polymers phase detection organic photovoltaics plasmon energy mapping electron energy loss spectroscopy EELS Core-loss mapping EFTEM |
| title | Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS Imaging |
| title_full | Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS Imaging |
| title_fullStr | Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS Imaging |
| title_full_unstemmed | Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS Imaging |
| title_short | Quantitative Phase Fraction Detection in Organic Photovoltaic Materials through EELS Imaging |
| title_sort | quantitative phase fraction detection in organic photovoltaic materials through eels imaging |
| topic | phase detection organic photovoltaics plasmon energy mapping electron energy loss spectroscopy EELS Core-loss mapping EFTEM |
| url | http://www.mdpi.com/2073-4360/7/11/1523 |
| work_keys_str_mv | AT ondrejdyck quantitativephasefractiondetectioninorganicphotovoltaicmaterialsthrougheelsimaging AT shenghu quantitativephasefractiondetectioninorganicphotovoltaicmaterialsthrougheelsimaging AT sanjibdas quantitativephasefractiondetectioninorganicphotovoltaicmaterialsthrougheelsimaging AT jongkeum quantitativephasefractiondetectioninorganicphotovoltaicmaterialsthrougheelsimaging AT kaixiao quantitativephasefractiondetectioninorganicphotovoltaicmaterialsthrougheelsimaging AT baminkhomami quantitativephasefractiondetectioninorganicphotovoltaicmaterialsthrougheelsimaging AT gerdduscher quantitativephasefractiondetectioninorganicphotovoltaicmaterialsthrougheelsimaging |