Effect of 3D π−π Stacking on Photovoltaic and Electroluminescent Properties in Triphenylamine-containing Poly(p-phenylenevinylene) Derivatives

Abstract

Poly(p-phenylenevinylene) (PPV) derivatives containing the 3D π−π stacking structures of the triphenylamine moieties as two side chains have been synthesized by the Wittig−Horner reaction. The presence of 2,5-bis(4-(N,N-diphenylamino)phenylenevinylene units along these π-conjugated polymer backbone lowered the band gap, and thus the resulting polymers exhibited strong and broad absorption in the visible region. Triphenylamine groups effectively extended the conjugation length through 3D π−π stacking and enhanced the hole-transporting properties of the polymers. Furthermore, the 3D π−π stacking effects of the triphenylamine moieties on the properties of the polymer light-emitting devices (PLEDs) and photovoltaic solar cells were also investigated in detail. The maximum electroluminescence (EL) brightness of the single-layer light emitting devices for P1 and P2 achieved 3003 and 1697 cd/m2, respectively. The bulk heterojunction polymer photovoltaic cells (PPVCs) based on P1 or P2 and PCBM (1:1, w/w) showed power conversion efficiencies up to 0.27% and 0.45% under the illumination of AM 1.5, 90 mW/cm2, which were 3−5 times higher than that of the device based on P3 (0.09%) without triphenylamine side chains.

Triphenylamine-based broad band-gap polymers for bulk-heterojunction polymer solar cells

“…Triphenylamine (TPA) as a fantastic unit has been concerned tremendously in organic light-emitting diodes (OLEDs) [22] and organic filed-effect transistors (OFETs) [23]. Also, TPA as a good electron-donating unit has been introduced to the dye-sensitized solar cells (DSSCs) [24] and small molecular BHJ organic solar cells (OSCs) [25], where it gave the versatile successes in achieving highefficacy photovoltaic performance.…”

Progress in Polymeric Electron-Donating Materials for Organic Solar Cells

“…性能研究表明 CN-PPV 具有较低的 HOMO 和 LUMO 能级, 适合作为电子受体材料, 和其 他聚合物电子给体材料配合使用, 制备全聚合物型太阳 能电池 [16] . 最近, Tang 和 Li 等 [17] 则在 PPV 主链的苯环 上通过 Wittig-Horner 反应引入两个三苯胺基团, 得到聚 合物 P2. 相比没有三苯基胺侧链的聚合物 P1 (E g ＝2.3…”

Synthesis and photovoltaic properties of dithienyl benzotriazole based poly(phenylene vinylene)s

“…Yield: 85%. 2,5-Dioctoxyl-1,4-xylene-bis (triphenyl phosphonium bromine) (6b) 30 A mixture of compound 5b (2.6 g, 5 mmol), triphenyl phosphine (3.93 g, 15 mmol), and 10 mL of freshly distilled DMF was heated to 95 C, and the reaction proceeded under the temperature while stirring for 24 h. The resulting mixture was poured into diethyl ether. The white solid was filtered and washed with diethyl ether repeatedly to remove the by-products, dried under vacuum to afford a white powder.…”