Direct evidence of type II band alignment in ZnO nanorods/poly (3-hexylthiophene) heterostructures

作者：Chan M H; Chen J Y; Lin T Y^*; Chen Y F

来源：Applied Physics Letters, 2012, 100(2): 021912.

DOI：10.1063/1.3676267

The emission from ZnO nanorods/poly(3-hexylthiophene) (P3HT) heterostructures with type II band alignment has been investigated. The additional emission due to the formation of the heterojunction around 950 nm has been found and attributed to the type II transition related to the recombination of electrons in conduction band of ZnO and holes in highest occupied molecular orbital band of P3HT. The consistency of excitation power density dependent photoluminescence (PL) spectra with the theoretical prediction offers a firm evidences for the type II transition. In addition, lifetime of P3HT measured by time-resolved PL also strongly supports that the infrared light indeed arises from the type II transition. Our results shown here provide the first direct evidence of the type II band alignment in ZnO nanorods/P3HT heterostructure, which should be very useful for the realization of underpinned mechanism of the developed optoelectronic devices.

• 出版日期2012-1-9