초록 |
In organic BHJ solar cells, the selection of an effective charge extraction and transportation buffer layer is one of the key components to achieve high performance. However, metal oxide buffer layer prepared by solution method open induced big variation of power conversion efficiency (PCE) because of difficulty of control sol-gel precursors. In this work, we demonstrated metal oxide buffer free organic BHJ solar cells using small molecules 7-(9,9’-spirobifluorene-2-yl)-N-(7-9,9’-spirobifluorene-2-yl)-9,9-dioctyl-9H-fluoren-2-yl)-N-(4-(9H-carbazol-9-yl)phenyl)-9,9-dioctyl-9H-fluoren-2-amine (CzPAF-SBF) as a material for hole transporting layer and phosphine oxide functionalized 1,3,5-triazine derivative(PO-TAZ) as a material for electron transporting layer. The solar cells using CzPAF-SBF and PO-TAZ showed almost comparable PCE values (> 10%) with the solar cells using metal oxide buffer layer. |