[10a-Z11-1~11] 12.5 有機太陽電池

▼ [10a-Z11-4] Eco-friendly AgBiS₂ Nanocrystal / ZnO Nanowire Heterojunction Solar Cells with Enhanced Carrier Collection

〇(D)Xiao Yun、Haibin Wang、Naoyuki Shibayama、Takaya Kubo、Hiroshi Segawa

キーワード：solar cell, eco-friendly quantum dot, ZnO nanowire

Solution-process compatibility and size-dependent bandgap tunability of colloidal quantum dots (CQDs) make them low-cost promising materials for next generation solar cells. Among CQD-based solar cells, devices formed with PbS CQDs and ZnO exhibit impressive performance. However, researches of eco-friendly CQDs-based solar cell are still limited. AgBiS₂ colloidal nanocrystals (NCs) with a wide absorption band (0.4-1.2 μm) are one of the alternatives to PbS CQDs. However, the power conversion efficiencies (PCEs) of planar-type solar cells using AgBiS₂ NCs (ITO / ZnO dense layer / AgBiS₂ NC layer/ hole transport layers (eg. PTB7:MoOx) / Ag) have been at most approximately 6% mainly due to the short carrier diffusion length of AgBiS2^[1]. In this work, we paid attention to nanowire (NW) structures, with the aim of elongation of carrier diffusion length, and we also applied widely used and less-expensive hole transport materials. We then fabricated NW-type solar cells (ITO / ZnO NW: AgBiS₂ mixture / AgBiS₂ overlayer / P3HT / Au) by using different ZnO NW lengths and the overlayer thicknesses to study charge collection in AgBiS₂ NW-type solar cells (NWSCs). ZnO NWs were synthesized by a hydrothermal method, and the length of ZnO NW was controlled by the reaction time ^[2].