2013.8.1 The 8th National and Global Chinese Conference of Organic Molecules & Polymer Light-emitting Materials and Their Opto-electronic Properties Efficient planar heterojunction organic solar cells using oriented tetraphenyldibenzoperiflanthene (DBP) as a donor（Zhongqiang Wang, Daisuke Yokoyama, Xiao-Feng Wang, Ziruo Hong, Takeshi Sano, Yang Yang, Junji Kido）