초록 |
As energy crisis has become a serious problem all over the world, polymer solar cells (PSCs) are considered as being one of the most important renewable resources due to the advantages such as low-cost, printable, flexible devices and easy processing. However, there are still problems to achieve high power conversion efficiencies (PCE) because of the mismatch between the solar spectrum and the spectra of organic materials used in active layer. To overcome this absorption limitation, synthesizing new low band gap polymers is proposed to improve PCE of polymer solar cells (PSCs). Generally, low band gap polymers consist of D (electron-rich unit) A(electron-deficient unit) alternative structure. Among electron-rich unit, benzodithiophenes (BDT) is an ideal conjugated unit for new photovoltaic material because of large plannar structure for better π-π stacking and small steric hindrance. Therefore, we have synthesized new low band gap polymers based on BDT. |