| 초록 |
PbSe nanocrystals (NCs) exhibit intriguing properties, e.g., size-dependent exciton energy levels and controllably exciton-exciton interactions, which could be uniquely suited to various applications. Of particular interest is the use of PbSe NCs in solar cells. Because of their over-unity multi-exciton generation efficiency, PbSe NCs are considered to be an active layer in solar cells for high photocurrent density. However, their rapid oxidation and poor instability hamper the widespread use of PbSe NCs in devices. In this study, we describe a simple halide treatment of colloidal PbSe NCs which become extraordinarily stable both in solution and in devices. Halide salts (e.g., NH4Cl, KCl, InCl, NH4Br, and NH4I) in methanol solution are injected into the crude synthesis solution of PbSe NCs, and the simple step does the magic. In this talk, the effect of halide treatment, the passivation mechanism, and the implications in transistors or solar cells will be discussed. |
