Air-Stable Inverted Organic Solar Cells with Pentacene Anode Buffer Layer

作者：Oida Tatsuya^*; Naito Tatsuhiro; Miyagawa Yuki; Sasaki Muneo; Harafuji Kenji

来源：Japanese Journal of Applied Physics, 2011, 50(8): 081601.

DOI：10.1143/JJAP.50.081601

A small-molecular organic solar cell with an inverted structure of indium-tin oxide (ITO)/bathocuproine (BCP)/fullerene (C-60)/copper phthalocyanine (CuPc)/pentacene/Ag is reported. Although the Ag electrode usually acts as the cathode because of its low work function, the Ag electrode appropriately works as the anode by inserting a pentacene thin layer between Ag and the active layer. The unencapsulated device shows a power conversion efficiency of 0.28% under 100mW/cm(2) AM1.5G simulated illumination, and a lifetime of 700 h. The lifetime is 700 times longer than that of a conventional device with a structure of ITO/CuPc/C-60/BCP/Ag. The long lifetime is attributed to the inverted structure in which the top electrode acts as the anode because this structure could effectively protect C-60 from the diffusion of oxygen. By substituting naphthalene-1,4,5,8-tetracarboxylic dianhydride for BCP as a cathode buffer, the power conversion efficiency and the lifetime are improved to 0.40% and more than 1200 h, respectively.

• 出版日期2011-8