Tianjin Kay Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, People's Republic of China.
Nanotechnology. 2012 Dec 7;23(48):485401. doi: 10.1088/0957-4484/23/48/485401. Epub 2012 Nov 2.
Coaxial nanorods with a single-crystalline core and nanocrystal sensitizer shell are a promising nanostructure to enhance the performance of semiconductor sensitized solar cells. Herein, we report the fabrication of coaxial nanorods by depositing n-type CdS and p-type CdTe nanocrystals sequentially on ZnO nanorods. We find that p-type CdTe nanocrystals can work jointly with n-type CdS nanocrystals to enhance the photocurrent and voltage, achieving a conversion efficiency more than three times that of pure ZnO/CdS nanorods. Electrochemical impedance spectroscopy characterization suggests that the stepwise band structure of ZnO/CdS/CdTe is conducive to improving charge separation and extending the electron diffusion length, finally contributing to a high conversion efficiency.
核壳型同轴纳米棒具有单晶核和纳米晶敏化壳，是提高半导体敏化太阳能电池性能的一种很有前途的纳米结构。本文报道了通过在 ZnO 纳米棒上依次沉积 n 型 CdS 和 p 型 CdTe 纳米晶来制备核壳型同轴纳米棒。我们发现，p 型 CdTe 纳米晶可以与 n 型 CdS 纳米晶共同作用，从而提高光电流和电压，实现了比纯 ZnO/CdS 纳米棒高出三倍多的转换效率。电化学阻抗谱表征表明，ZnO/CdS/CdTe 的分步能带结构有利于提高电荷分离和延长电子扩散长度，最终实现高转换效率。
