Preparation of flexible organic solar cells with highly conductive and transparent metal-oxide multilayer electrodes based on silver oxide.
We report that significantly more transparent yet comparably conductive AgOx films, when compared to Ag films, are synthesized by the inclusion of a remarkably small amount of oxygen (i.e., 2 or 3 atom %) in thin Ag films. An 8 nm thick AgOx (O/Ag=2.4 atom %) film embedded between 30 nm thick ITO films (ITO/AgOx/ITO) achieves a transmittance improvement of 30% when compared to a conventional ITO/Ag/ITO electrode with the same configuration by retaining the sheet resistance in the range of 10-20 Ω sq(-1). The high transmittance provides an excellent opportunity to improve the power-conversion efficiency of organic solar cells (OSCs) by successfully matching the transmittance spectral range of the electrode to the optimal absorption region of low band gap photoactive polymers, which is highly limited in OSCs utilizing conventional ITO/Ag/ITO electrodes. An improvement of the power-conversion efficiency from 4.72 to 5.88% is achieved from highly flexible organic solar cells (OSCs) fabricated on poly(ethylene terephthalate) polymer substrates by replacing the conventional ITO/Ag/ITO electrode with the ITO/AgOx/ITO electrode. This novel transparent electrode can facilitate a cost-effective, high-throughput, room-temperature fabrication solution for producing large-area flexible OSCs on heat-sensitive polymer substrates with excellent power-conversion efficiencies.
Surface Technology Division, Korea Institute of Materials Science , Changwon, Gyeongnam 641-831, Republic of Korea.
Jungheum
J
Yun
Wei
W
Wang
Tae Sung
TS
Bae
Yeon Hyun
YH
Park
Yong-Cheol
YC
Kang
Dong-Ho
DH
Kim
Sunghun
S
Lee
Gun-Hwan
GH
Lee
Myungkwan
M
Song
Jae-Wook
JW
Kang
D004553:Electric Conductivity; D004566:Electrodes; D010087:Oxides / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D018030:Silver Compounds / Q000737:chemistry*; D012993:Solar Energy; D017971:Tin Compounds / Q000737:chemistry
D010087:Oxides; D011108:Polymers; D018030:Silver Compounds; D017971:Tin Compounds; C109984:indium tin oxide; C040225:disilver oxide; D010100:Oxygen