Cargando…

Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy

[Image: see text] The molecular orientation of organic molecules of zinc phthalocyanine (ZnPc) in single-component films on copper iodide (CuI) substrates can be controlled to achieve a molecular orientation lying flat on the substrate (flat-on) owing to π–d orbital interactions between the ZnPc mol...

Descripción completa

Detalles Bibliográficos
Autores principales: Chikamatsu, Tatsuki, Shahiduzzaman, Md., Yamamoto, Kohei, Karakawa, Makoto, Kuwabara, Takayuki, Takahashi, Kohshin, Taima, Tetsuya
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2018
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6641761/
https://www.ncbi.nlm.nih.gov/pubmed/31458767
http://dx.doi.org/10.1021/acsomega.8b00099
_version_ 1783436848382607360
author Chikamatsu, Tatsuki
Shahiduzzaman, Md.
Yamamoto, Kohei
Karakawa, Makoto
Kuwabara, Takayuki
Takahashi, Kohshin
Taima, Tetsuya
author_facet Chikamatsu, Tatsuki
Shahiduzzaman, Md.
Yamamoto, Kohei
Karakawa, Makoto
Kuwabara, Takayuki
Takahashi, Kohshin
Taima, Tetsuya
author_sort Chikamatsu, Tatsuki
collection PubMed
description [Image: see text] The molecular orientation of organic molecules of zinc phthalocyanine (ZnPc) in single-component films on copper iodide (CuI) substrates can be controlled to achieve a molecular orientation lying flat on the substrate (flat-on) owing to π–d orbital interactions between the ZnPc molecules and the CuI. A 3-fold enhancement in the performance of organic photovoltaic cells has been reported by introducing a CuI interlayer between a ZnPc:fullerene (C60) bulk heterojunction (BHJ) film and the substrate. However, the mechanism underpinning the resultant solar cell performance enhancement was unclear. Herein, we report on the results of using in situ reflection absorption spectroscopy measurements during the vacuum deposition of coevaporated ZnPc:C60 BHJ films on various substrates to investigate the ZnPc molecular orientation. Our results revealed that the flat-on molecular orientation of ZnPc molecules in ZnPc:C60 BHJ films on CuI interlayers and flat-on ZnPc substrates can be successfully identified via the strong π–π interactions between the BHJ film and the substrate. The π–π interactions between individual ZnPc molecules are stronger than the π–d interactions between ZnPc molecules and CuI in coevaporated ZnPc:C60 films, as is evident from the molecular orientation of ZnPc, as determined by in situ reflection absorption spectroscopy. Our findings demonstrate that precisely controlling the molecular orientations of the films could enhance organic photovoltaic (OPV) performance. The present work provides important insights that will enable the design of higher performance OPV cells.
format Online
Article
Text
id pubmed-6641761
institution National Center for Biotechnology Information
language English
publishDate 2018
publisher American Chemical Society
record_format MEDLINE/PubMed
spelling pubmed-66417612019-08-27 Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy Chikamatsu, Tatsuki Shahiduzzaman, Md. Yamamoto, Kohei Karakawa, Makoto Kuwabara, Takayuki Takahashi, Kohshin Taima, Tetsuya ACS Omega [Image: see text] The molecular orientation of organic molecules of zinc phthalocyanine (ZnPc) in single-component films on copper iodide (CuI) substrates can be controlled to achieve a molecular orientation lying flat on the substrate (flat-on) owing to π–d orbital interactions between the ZnPc molecules and the CuI. A 3-fold enhancement in the performance of organic photovoltaic cells has been reported by introducing a CuI interlayer between a ZnPc:fullerene (C60) bulk heterojunction (BHJ) film and the substrate. However, the mechanism underpinning the resultant solar cell performance enhancement was unclear. Herein, we report on the results of using in situ reflection absorption spectroscopy measurements during the vacuum deposition of coevaporated ZnPc:C60 BHJ films on various substrates to investigate the ZnPc molecular orientation. Our results revealed that the flat-on molecular orientation of ZnPc molecules in ZnPc:C60 BHJ films on CuI interlayers and flat-on ZnPc substrates can be successfully identified via the strong π–π interactions between the BHJ film and the substrate. The π–π interactions between individual ZnPc molecules are stronger than the π–d interactions between ZnPc molecules and CuI in coevaporated ZnPc:C60 films, as is evident from the molecular orientation of ZnPc, as determined by in situ reflection absorption spectroscopy. Our findings demonstrate that precisely controlling the molecular orientations of the films could enhance organic photovoltaic (OPV) performance. The present work provides important insights that will enable the design of higher performance OPV cells. American Chemical Society 2018-05-25 /pmc/articles/PMC6641761/ /pubmed/31458767 http://dx.doi.org/10.1021/acsomega.8b00099 Text en Copyright © 2018 American Chemical Society This is an open access article published under an ACS AuthorChoice License (http://pubs.acs.org/page/policy/authorchoice_termsofuse.html) , which permits copying and redistribution of the article or any adaptations for non-commercial purposes.
spellingShingle Chikamatsu, Tatsuki
Shahiduzzaman, Md.
Yamamoto, Kohei
Karakawa, Makoto
Kuwabara, Takayuki
Takahashi, Kohshin
Taima, Tetsuya
Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy
title Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy
title_full Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy
title_fullStr Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy
title_full_unstemmed Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy
title_short Identifying Molecular Orientation in a Bulk Heterojunction Film by Infrared Reflection Absorption Spectroscopy
title_sort identifying molecular orientation in a bulk heterojunction film by infrared reflection absorption spectroscopy
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6641761/
https://www.ncbi.nlm.nih.gov/pubmed/31458767
http://dx.doi.org/10.1021/acsomega.8b00099
work_keys_str_mv AT chikamatsutatsuki identifyingmolecularorientationinabulkheterojunctionfilmbyinfraredreflectionabsorptionspectroscopy
AT shahiduzzamanmd identifyingmolecularorientationinabulkheterojunctionfilmbyinfraredreflectionabsorptionspectroscopy
AT yamamotokohei identifyingmolecularorientationinabulkheterojunctionfilmbyinfraredreflectionabsorptionspectroscopy
AT karakawamakoto identifyingmolecularorientationinabulkheterojunctionfilmbyinfraredreflectionabsorptionspectroscopy
AT kuwabaratakayuki identifyingmolecularorientationinabulkheterojunctionfilmbyinfraredreflectionabsorptionspectroscopy
AT takahashikohshin identifyingmolecularorientationinabulkheterojunctionfilmbyinfraredreflectionabsorptionspectroscopy
AT taimatetsuya identifyingmolecularorientationinabulkheterojunctionfilmbyinfraredreflectionabsorptionspectroscopy