Charge transfer plasmon coupled surface photosensing in ZnO nanorods–Au array hetero-nanostructures. (February 2021)

• Record Type: Journal Article
• Authors: Ghaemi-moghadam, Mahla; Hasanzadeh, Abdollah; Rahmati, Ali
• Is Part Of: Optics and lasers in engineering. Volume 137(2021)
• Publication Date: 2021-02
• Subjects: Zinc Oxide Nanorods (ZNO NRS) array -- Nonlinear optical properties -- Charge transfer plasmon -- Surface Enhanced-Raman Scattering (SERS), Photosensitivity; Lasers in engineering -- Periodicals; Optical measurements -- Periodicals; Optics -- Periodicals; Lasers en ingénierie -- Périodiques; Mesures optiques -- Périodiques; Optique -- Périodiques; 621.36605
• DOI: 10.1016/j.optlaseng.2020.106384
• Languages: English
• ISSNs: 0143-8166

Abstract

Highlights: Creating a three-dimensionally (3D) dispersed plasmonic ZnO NRs-Au array hetero nanostructure (HNS). The SPR excitation and charge transfer plasmon within the locally enhanced electromagnetic field produced surface enhanced raman signal of ZnO NRs-Au array HNS. An enhanced factor (EF) of 500 can be obtained for the surface enhancement raman scattering (SERS) response for ZnO NRs-Au array HNS. Photoluminescence spectrum shows Au- mediated blue emission enhancement. Photosensitivity, photocatalytic activity, nonlinear optical refractive index and absorption are elevated in ZnO NRs-Au array HNS. The ZnO NRs based structures shows high nonlinear refractive index and nonlinear optical absorption coefficient which qualify them for utilizing in optical switching device with excellent figures of merit. The ZnO NRs-Au array HNS shows maximal photocurrent enhancement of 69%. Abstract: Well-aligned zinc oxide nanorods (ZnO NRs) array have been grown by wet chemical method on seeded substrates at low temperature. Gold nanosheet has been deposited by DC magnetron sputtering on the surrounding of the ZnO NRs array at glancing angle, thus creating a three-dimensionally (3D) plasmonic hetero-nanostructure (HNS). The localized surface plasmon resonance (LSPR) is tuned and blue-shifted as the thickness of the gold nanosheet increased. The efficient surface plasmon (SP) excitation, and charge transfer plasmon through tunneling transport and junction conductance elevates the locally electromagnetic field and subsequently enhances surface Raman scattering in ZnO NRs-Au array HNS. An enhanced factor (EF) of 500 can be obtained for the surface enhancement Raman scattering (SERS) response for ZnO NRs-Au array HNS. Photoluminescence spectrum shows Au- mediated blue emission enhancement. The ZnO NRs–Au HNSs show high nonlinear refractive index and nonlinear optical absorption coefficient around 10 −5 cm 2 /W and 1 cm/W, respectively. The ZnO NRs-Au array HNS can provide the figures of merit w = 209.83 and t = 0.59 for the optical switching devices. Photosensitivity and photocatalytic activity are elevated in ZnO NRs-Au array HNS. The ZnO NRs-Au array HNS shows maximal photocurrent enhancement of 69.38% in comparison to the bare ZnO NRs array.