TY - JOUR
T1 - Comparison of small amounts of polycrystalline donor materials in C 70-based bulk heterojunction photovoltaics and optimization of dinaphthothienothiophene based photovoltaic
AU - Zheng, Yan Qiong
AU - Potscavage, William J.
AU - Zhang, Qi Sheng
AU - Komino, Takeshi
AU - Taneda, Masatsugu
AU - Adachi, Chihaya
N1 - Funding Information:
This work was supported financially by the Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST) and by the International Institute for Carbon Neutral Energy Research (WPI-I2CNER), sponsored by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan.
PY - 2014/4
Y1 - 2014/4
N2 - Comparative studies of the effects of a series of polycrystalline donors on the performance of 95 wt.%-C70-based bulk-heterojunction (BHJ) photovoltaics were conducted. A BHJ based on the wide band-gap molecule dinaphthothienothiophene (DNTT) shows power conversion efficiency (ηPCE) of up to 4.28%. The photovoltaic parameters are superior to those of devices using the similar molecule pentacene (PEN) or polycrystalline copper phthalocyanine (CuPc) for donor concentrations from 5 to 30 wt.%. The low-lying DNTT ionization potential and the high μh in the DNTT blend support the excellent DNTT device performance. The low performance of BHJs with 5 wt.% PEN and 5 wt.% CuPc may stem from strong exciplex recombination in the PEN:C70 blend and limited hole mobility combined with geminate polaron-pair recombination in the CuPc:C70 blend. The zero-field hole mobility of the blends with 5 wt.% donor has a positive correlation with the corresponding device performance. The ηPCE of a 5 wt.%-DNTT BHJ cell was improved to 4.92% by optimizing the cathode buffer layer.
AB - Comparative studies of the effects of a series of polycrystalline donors on the performance of 95 wt.%-C70-based bulk-heterojunction (BHJ) photovoltaics were conducted. A BHJ based on the wide band-gap molecule dinaphthothienothiophene (DNTT) shows power conversion efficiency (ηPCE) of up to 4.28%. The photovoltaic parameters are superior to those of devices using the similar molecule pentacene (PEN) or polycrystalline copper phthalocyanine (CuPc) for donor concentrations from 5 to 30 wt.%. The low-lying DNTT ionization potential and the high μh in the DNTT blend support the excellent DNTT device performance. The low performance of BHJs with 5 wt.% PEN and 5 wt.% CuPc may stem from strong exciplex recombination in the PEN:C70 blend and limited hole mobility combined with geminate polaron-pair recombination in the CuPc:C70 blend. The zero-field hole mobility of the blends with 5 wt.% donor has a positive correlation with the corresponding device performance. The ηPCE of a 5 wt.%-DNTT BHJ cell was improved to 4.92% by optimizing the cathode buffer layer.
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U2 - 10.1016/j.orgel.2014.01.012
DO - 10.1016/j.orgel.2014.01.012
M3 - Article
AN - SCOPUS:84894562223
VL - 15
SP - 878
EP - 885
JO - Organic Electronics: physics, materials, applications
JF - Organic Electronics: physics, materials, applications
SN - 1566-1199
IS - 4
ER -