TY - JOUR
T1 - Thermally stable bulk heterojunction prepared by sequential deposition of nanostructured polymer and fullerene
AU - Hwang, Heewon
AU - Lee, Hoyeon
AU - Shafian, Shafidah
AU - Lee, Wooseop
AU - Seok, Jeesoo
AU - Ryu, Ka Yeon
AU - Ryu, Du Yeol
AU - Kim, Kyungkon
N1 - Funding Information:
Acknowledgments: This research was supported by NRF under the program numbers NRF-2015M1A2A2057506 and NRF-2016M1A2A2940914 and by the New & Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), who granted financial resources from the Ministry of Trade, Industry & Energy, Republic of Korea. (No. 20123010010140 and 20163030013900). The authors thank Mr. Sungmin Park and Mr. Yeongsik Kim for assistance with the GIWAXS characterization. The X-ray experiments at PLS-II (Beamline 9A U-SAXS), Korea, were supported in part by MSIP and POSTECH.
Publisher Copyright:
© 2017 by the authors.
PY - 2017/9/17
Y1 - 2017/9/17
N2 - A morphologically-stable polymer/fullerene heterojunction has been prepared by minimizing the intermixing between polymer and fullerene via sequential deposition (SqD) of a polymer and a fullerene solution. A low crystalline conjugated polymer of PCPDTBT (poly[2,6-(4,4- bis-(2-ethylhexyl)-4H-cyclopenta [2,1-b;3,4-b0]dithiophene)-alt-4,7(2,1,3-benzothiadiazole)]) has been utilized for the polymer layer and PC71BM (phenyl-C71-butyric-acid-methyl ester) for the fullerene layer, respectively. Firstly, a nanostructured PCPDTBT bottom layer was developed by utilizing various additives to increase the surface area of the polymer film. The PC71BM solution was prepared by dissolving it in the 1,2-dichloroethane (DCE), exhibiting a lower vapor pressure and slower diffusion into the polymer layer. The deposition of the PC71BM solution on the nanostructured PCPDTBT layer forms an inter-digitated bulk heterojunction (ID-BHJ) with minimized intermixing. The organic photovoltaic (OPV) device utilizing the ID-BHJ photoactive layer exhibits a highly reproducible solar cell performance. In spite of restricted intermixing between the PC71BM and the PCPDTBT, the efficiency of ID-BHJ OPVs (3.36%) is comparable to that of OPVs (3.87%) prepared by the conventional method (deposition of a blended solution of polymer:fullerene). The thermal stability of the ID-BHJ is superior to the bulk heterojunction (BHJ) prepared by the conventional method. The ID-BHJ OPV maintains 70% of its initial efficiency after thermal stress application for twelve days at 80 °C, whereas the conventional BHJ OPV maintains only 40% of its initial efficiency.
AB - A morphologically-stable polymer/fullerene heterojunction has been prepared by minimizing the intermixing between polymer and fullerene via sequential deposition (SqD) of a polymer and a fullerene solution. A low crystalline conjugated polymer of PCPDTBT (poly[2,6-(4,4- bis-(2-ethylhexyl)-4H-cyclopenta [2,1-b;3,4-b0]dithiophene)-alt-4,7(2,1,3-benzothiadiazole)]) has been utilized for the polymer layer and PC71BM (phenyl-C71-butyric-acid-methyl ester) for the fullerene layer, respectively. Firstly, a nanostructured PCPDTBT bottom layer was developed by utilizing various additives to increase the surface area of the polymer film. The PC71BM solution was prepared by dissolving it in the 1,2-dichloroethane (DCE), exhibiting a lower vapor pressure and slower diffusion into the polymer layer. The deposition of the PC71BM solution on the nanostructured PCPDTBT layer forms an inter-digitated bulk heterojunction (ID-BHJ) with minimized intermixing. The organic photovoltaic (OPV) device utilizing the ID-BHJ photoactive layer exhibits a highly reproducible solar cell performance. In spite of restricted intermixing between the PC71BM and the PCPDTBT, the efficiency of ID-BHJ OPVs (3.36%) is comparable to that of OPVs (3.87%) prepared by the conventional method (deposition of a blended solution of polymer:fullerene). The thermal stability of the ID-BHJ is superior to the bulk heterojunction (BHJ) prepared by the conventional method. The ID-BHJ OPV maintains 70% of its initial efficiency after thermal stress application for twelve days at 80 °C, whereas the conventional BHJ OPV maintains only 40% of its initial efficiency.
KW - Bulk heterojunction
KW - Organic solar cell
KW - Sequential deposition
KW - Stability
UR - http://www.scopus.com/inward/record.url?scp=85029781977&partnerID=8YFLogxK
U2 - 10.3390/polym9090456
DO - 10.3390/polym9090456
M3 - Article
AN - SCOPUS:85029781977
SN - 2073-4360
VL - 9
JO - Polymers
JF - Polymers
IS - 9
M1 - 456
ER -