TY - JOUR
T1 - Effect of blend composition on binary organic solar cells using a low band gap polymer
AU - Wright, Matthew
AU - Lin, Rui
AU - Tayebjee, Murad J. Y.
AU - Yang, Xiaohan
AU - Veettil, Binesh Puthen
AU - Wen, Xiaoming
AU - Uddin, Ashraf
PY - 2015/3
Y1 - 2015/3
N2 - This report investigates the influence of the solution blend composition of binary bulk heterojunction organic solar cells composed of poly[2,1,3-benzothiadiazole-4,7-diyl[4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b′]dithiophene-2,6-diyl]] (PCPDTBT) and [6,6]-phenyl C71 butyric acid methyl ester (PC71BM). The blend polymer: fullerene composition was varied from 1:1 (50 wt% PC71BM) to 2:9 (82 wt% PC71BM). Increasing the amount of polymer in the blend results in the greatest overall absorption, as the donor material PCPDTBT is the main contributor to absorption. However, high polymer content leads to poor photovoltaic performance. For this material combination, the optimum blend polymer: fullerene composition was found to be 2:7. Increasing the fullerene content in the blend led to a significant improvement in the internal quantum efficiency of devices. This was correlated with an increase of the electron mobility, as the fullerene content was increased. Improved electron transport, leading to more balanced transport between electrons and holes, significantly improved the short circuit current density (Jsc) and fill factor (FF).
AB - This report investigates the influence of the solution blend composition of binary bulk heterojunction organic solar cells composed of poly[2,1,3-benzothiadiazole-4,7-diyl[4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b′]dithiophene-2,6-diyl]] (PCPDTBT) and [6,6]-phenyl C71 butyric acid methyl ester (PC71BM). The blend polymer: fullerene composition was varied from 1:1 (50 wt% PC71BM) to 2:9 (82 wt% PC71BM). Increasing the amount of polymer in the blend results in the greatest overall absorption, as the donor material PCPDTBT is the main contributor to absorption. However, high polymer content leads to poor photovoltaic performance. For this material combination, the optimum blend polymer: fullerene composition was found to be 2:7. Increasing the fullerene content in the blend led to a significant improvement in the internal quantum efficiency of devices. This was correlated with an increase of the electron mobility, as the fullerene content was increased. Improved electron transport, leading to more balanced transport between electrons and holes, significantly improved the short circuit current density (Jsc) and fill factor (FF).
KW - Blend composition
KW - Organic solar cell
KW - PCPDTBT
UR - http://www.scopus.com/inward/record.url?scp=84920836445&partnerID=8YFLogxK
U2 - 10.1166/jnn.2015.9873
DO - 10.1166/jnn.2015.9873
M3 - Article
C2 - 26413641
AN - SCOPUS:84920836445
VL - 15
SP - 2204
EP - 2211
JO - Journal of Nanoscience and Nanotechnology
JF - Journal of Nanoscience and Nanotechnology
SN - 1533-4880
IS - 3
ER -