Miniband formation in quantum dot amorphous and its application to photovoltaic devices

我们致力于开发具有极高转换效率的量子点（QD）太阳能电池。为此，我们研究了胶体InAs量子点的合成方法；InAs量子点比目前用于量子点太阳能电池研究的PbSe量子点显示出更低的多激子生成阈值能量。我们关注的是相对安全且易于处理的三苯基胂，而不是传统的三（三甲基硅基）胂作为砷源。我们成功地开发了一种合成胶体InAs量子点的新途径。此外，我们还研究了非晶量子点中微带的形成，其量子点密度明显大于传统的自组装量子点薄膜，但量子点排列不存在周期性。在PbSe量子点上可以清楚地观察到微带形成，而在CdSe和PbS量子点上没有观察到微带形成。这表明微带的形成与激子玻尔半径有很大的关系。

We focused on to develop quantum dot (QD) solar cells that show extremely high conversion efficiency. For this purpose, we investigated synthesis method of colloidal InAs QDs; the InAs QDs show lower threshold energy for multiple exciton generation than PbSe QDs that are currently used in QD solar cell investigations. We focused on the triphenyl arsine that is comparatively safe and easy to handle rather than the conventional tris(trimethylsilyl)arsine as an arsenic source. We successfully developed a new synthesis route to colloidal InAs QDs. Further, we investigated miniband formation in quantum dot amorphous, of which the density of QD is significant larger than that in conventional self-assembled QD films but no periodicity is exist in the QD arrangement. Miniband formation was clearly observed for the PbSe quantum dots, but it was not observed for the CdSe and PbS QDs. This indicates that the miniband formation is significantly dependent on the exciton Bohr radius.