10.1021/acsami.6b15436.s001
Pengzhi Guo
Pengzhi
Guo
Guoping Luo
Guoping
Luo
Qiang Su
Qiang
Su
Jianfeng Li
Jianfeng
Li
Peng Zhang
Peng
Zhang
Junfeng Tong
Junfeng
Tong
Chunyan Yang
Chunyan
Yang
Yangjun Xia
Yangjun
Xia
Hongbin Wu
Hongbin
Wu
Boosting
Up Performance of Inverted Photovoltaic Cells from Bis(alkylthien-2-yl)dithieno[2,3‑<i>d</i>:2′,3′‑<i>d</i>′]benzo[1,2‑<i>b</i>:4′,5′‑<i>b</i>′]di
thiophene-Based Copolymers by Advantageous Vertical Phase Separation
American Chemical Society
2017
XPS
PDTBDT-FBT
devices configuration
Inverted Photovoltaic Cells
power conversion efficiencies
PCE
polymers cathode modification layers
light harvesting characteristics
PC 71 BM
Advantageous Vertical Phase Separation
PDTBDT-BT
electron acceptor moieties
phase separation
ITO
electron donor moieties
cathode modification interlayer
AM
X-ray photoelectron spectroscopy
PFN
2017-03-09 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Boosting_Up_Performance_of_Inverted_Photovoltaic_Cells_from_Bis_alkylthien-2-yl_dithieno_2_3_i_d_i_2_3_i_d_i_benzo_1_2_i_b_i_4_5_i_b_i_di_thiophene-Based_Copolymers_by_Advantageous_Vertical_Phase_Separation/4765690
The
photovoltaic cells (PVCs) from conjugated copolymers of PDTBDT-BT
and PDTBDT-FBT with 5,10-bis(4,5-didecylthien-2-yl)dithieno[2,3-<i>d</i>:2′,3′-<i>d</i>′]benzo[1,2-<i>b</i>:4,5-<i>b</i>′]dithiophene as electron
donor moieties and benzothiadiazole and/or 5,6-difluorobenzothiadiazole
as electron acceptor moieties are optimized by employing alcohol-soluble
PFN (poly(9,9-bis(3′-(<i>N</i>,<i>N</i>-dimethylamino)propyl)-2,7-fluorene)-<i>alt</i>-2,7-(9,9-dioctylfluorene))
as cathode modification interlayer. The power conversion efficiencies
(PCEs) of inverted PVCs (<i>i-</i>PVCs) from PDTBDT-BT and
PDTBDT-FBT with devices configuration as ITO/PFN/active layer/MoO<sub>3</sub>/Ag are increased from 4.97% to 8.54% and 5.92% to 8.74%,
in contrast to those for the regular PVCs (<i>r-</i>PVCs)
with devices configuration as ITO/PEDOT:PSS/active layer/Ca/Al under
100 mW/cm<sup>2</sup> AM 1.5 illumination. The optical modeling calculations
and X-ray photoelectron spectroscopy (XPS) investigations reveal that
the <i>r-</i>PVCs and <i>i-</i>PVCs from the copolymers
exhibit similar light harvesting characteristics, and the enhancements
of the PCEs of the <i>i-</i>PVCs from the copolymers are
mainly contributed to the favorable vertical phase separation as the
strongly polymer-enriched top surface layers and slightly PC<sub>71</sub>BM (phenyl-C<sub>71</sub>-butyric acid methyl ester)-enriched bottom
surface layers are correspondingly connected to the anodes and cathodes
of the <i>i-</i>PVCs, while they are opposite in the <i>r-</i>PVCs. As we known, it is the first time to experimentally
verify that the <i>i-</i>PVCs with alcohol-soluble conjugated
polymers cathode modification layers enjoy favorable vertical phase
separation.