Hot-electron injection in Au nanorod-ZnO nanowire hybrid device for near-infrared photodetection

Thumbnail Image
10443.pdf(921.49 KB)
Accepted version
10443_1.pdf(579.17 KB)
Supporting information
Pescaglini, Andrea
Martín, Alfonso
Cammi, Davide
Juska, Gediminas
Ronning, Carsten
Pelucchi, Emanuele
Iacopino, Daniela
Journal Title
Journal ISSN
Volume Title
American Chemical Society, ACS
Published Version
Research Projects
Organizational Units
Journal Issue
In this Letter, we present a new class of near-infrared photodetectors comprising Au nanorods-ZnO nanowire hybrid systems. Fabricated hybrid FET devices showed a large photoresponse under radiation wavelengths between 650 and 850 nm, accompanied by an "ultrafast" transient with a time scale of 250 ms, more than 1 order of magnitude faster than the ZnO response under radiation above band gap. The generated photocurrent is ascribed to plasmonic-mediated generation of hot electrons at the metal-semiconductor Schottky barrier. In the presented architecture, Au-nanorod-localized surface plasmons were used as active elements for generating and injecting hot electrons into the wide band gap ZnO nanowire, functioning as a passive component for charge collection. A detailed investigation of the hot electron generation and injection processes is discussed to explain the improved and extended performance of the hybrid device. The quantum efficiency measured at 650 nm was calculated to be approximately 3%, more than 30 times larger than values reported for equivalent metal/semiconductor planar photodetectors. The presented work is extremely promising for further development of novel miniaturized, tunable photodetectors and for highly efficient plasmonic energy conversion devices.
Plasmon , Hot electron nanowire , Au nanorod , Photodetector , 2D nanoparticle arrays , Metal nanocrystals , Interfaces , Photocurrent , Carriers , Films
Pescaglini, A., Martín, A., Cammi, D., Juska, G., Ronning, C., Pelucchi, E. and Iacopino, D. (2014) 'Hot-Electron Injection in Au Nanorod–ZnO Nanowire Hybrid Device for Near-Infrared Photodetection', Nano Letters, 14(11), pp. 6202-6209.
© 2014 American Chemical Society. This document is the Accepted Manuscript version of a Published Work that appeared in final form in Nano Letters, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see