Electronic Materials Research Laboratory (EMRL), Key Laboratory of Education Ministry, International Center for Dielectric Research, Xi'an Jiaotong University, Xi'an, China.
ACS Appl Mater Interfaces. 2013 Jun 12;5(11):5139-48. doi: 10.1021/am4009924. Epub 2013 May 23.
In the field of quantum dots (QDs)-sensitized solar cells, semiconductor QDs sensitizer with a moderate band gap is required in order to sufficiently match the solar spectrum and achieve efficient charge separation. At present, changing the size of QDs is the main method used for adjusting their band gap through quantum size effect, however, the pore sizes of mesoporous TiO2 film set a limit on the allowed size of QDs. Therefore, the tuning of electronic and optical properties by changing the particle size could be limited under some circumstances. In this paper, high-quality aqueous CdS(x)Se(1-x) QDs sensitizer is successfully synthesized and effectively deposited on a mesoporous TiO2 film by a one-step hydrothermal method. In addition to size, alloy QDs provide composition as an additional dimension for tailoring their electronic properties. The alloy composition and band gap can be precisely controlled by tuning the precursor (Se/Na2S·9H2O) ratio while maintaining the similar particle size. By using such CdS(x)Se(1-x) sensitized TiO2 films as photoanodes for solar cell, a maximum power conversion efficiency of 2.23% is achieved under one sun illumination (AM 1.5 G, 100 mW cm(-2)).
在量子点（QD）敏化太阳能电池领域，需要具有适中带隙的半导体 QD 敏化剂，以便充分匹配太阳光谱并实现有效的电荷分离。目前，通过量子尺寸效应改变 QD 的尺寸是调节其带隙的主要方法，但是介孔 TiO2 薄膜的孔径大小限制了 QD 的允许尺寸。因此，在某些情况下，通过改变颗粒尺寸来调整电子和光学性能可能会受到限制。本文采用一步水热法成功合成了高质量的水性 CdS(x)Se(1-x)QD 敏化剂，并将其有效沉积在介孔 TiO2 薄膜上。除了尺寸之外，合金 QD 还提供了组成作为另一个维度来调整其电子特性。通过调整前驱体（Se/Na2S·9H2O）的比例，可以精确控制合金组成和带隙，同时保持相似的颗粒尺寸。使用此类 CdS(x)Se(1-x)敏化 TiO2 薄膜作为太阳能电池的光阳极，在模拟太阳光（AM 1.5G，100 mW cm(-2))下实现了 2.23%的最大功率转换效率。
