Investigation of the Photophysical and Electrical Characteristics of CuInS₂ QDs/SWCNT Hybrid Nanostructure

A novel photoactive hybrid nanostructure based on zero-dimensional (0-D) light-harvesting components of CuInS 2 quantum dots (QDs) and one-dimensional (1-D) transporting channel of single-wall carbon nanotube (SWCNT) was synthesized by hydrophobic interaction between alkyl chain of dodecanethiol molecule (QDs surface) and octadecylamine (CNT surface). Photophysical and electrical characterizations suggest that an efficient electron transfer from photoexcited CIS QDs to SWCNT takes place. Furthermore, size-dependent optical study shows that faster electron transfer takes place from CIS to SWCNT for small-size QDs compared to large-size quantum dots. The rate constant for electron transfer from photoexcited CIS to SWCNT increased from 1.9 × 10 6 to 3.5 × 10 6 s –1 with decrease in the size of CIS QDs from 5.0 to 3.5 nm.