Main content area

Improving the Photoresponse Properties of CdSe Quantum Wires by Alignment and Ligand Exchange

Shi, Jiaoyi, Liu, Limin, Xu, Fangjie, Zhang, Yi
ACS applied materials & interfaces 2018 v.11 no.1 pp. 1192-1200
chemical composition, electric field, electrical conductivity, geometry, ligands, nanowires, semiconductors
Semiconductor nanowires are the ideal building blocks to construct various thin-film electronic and optoelectronic devices, the performance of which is largely determined by their ensemble geometry and surface chemistry in addition to the chemical composition. Here, we report the large-scale and oriented assembly of CdSe nanowires on the basis of a light-induced assembly approach under an external electric field. To further increase the electrical conductivity of nanowire films, the original surface-capping organic ligands are exchanged with small ionic species through a solid-state ligand-exchange process. The resulting surface-modified CdSe nanowire films exhibit markedly enhanced photoresponse properties including high on/off ratios and fast response. This work establishes a simple yet scalable method to fabricate aligned nanowire films with a desired surface chemistry, which can be broadly used in various electronic and optoelectronic devices.