An effective surface-enhanced Raman scattering template based on a Ag nanocluster–ZnO nanowire array

Abstract

An effective surface-enhanced Raman scattering (SERS) template based on a 3D hybrid Ag nanocluster (NC)-decorated ZnO nanowire array was fabricated through a simple process of depositing Ag NCs on ZnO nanowire arrays. The effects of particle size and excitation energy on the Raman scattering in these hybrid systems have been investigated using rhodamine 6G as a standard analyte. The results indicate that the hybrid nanosystem with 150 nm Ag NCs produces a larger SERS enhancement factor of 3.2 x 10(8), which is much higher than that of 10 nm Ag NCs (6.0 x 10(6)) under 532 nm excitation energy. The hybrid nanowire arrays were further applied to obtain SERS spectra of the two-photon absorption (TPA) chromophore T7. Finite-difference time-domain simulations reveal the presence of an enhanced field associated with inter-wire plasmon coupling of the 150 nm Ag NCs on adjacent ZnO nanowires; such a field was absent in the case of the 10 nm Ag NC-coated ZnO nanowire. Such hybrid nanosystems could be used as SERS substrates more effectively than assembled Ag NC film due to the enhanced light-scattering local field and the inter-wire plasmon-enhanced electromagnetic field.

Ion beam induced evolution of surface morphology and optical properties of SnO2–ZnO nanocomposite thin films

“…Chen et al [48] have reported the use of ZnO/Au composite nanoarrays as substrates for surface-enhanced Raman scattering (SERS) based sensing and showed that the density of Au nanoparticles and the morphology of ZnO/Au nanostructures are the two main factors 7 affecting the SERS enhancement. Similar results on SERS enhancement were reported by Deng et al[49] using Ag nanocluster-ZnO nanowire array. Our Raman results showed that increase in fluence to 2x1015 ions/cm 2 resulted in significant increase in the intensity of E 1 (LO) mode.…”

Ag nanoclusters on ZnO nanodome array as hybrid SERS-active substrate for trace detection of malachite green

“…Some examples were listed in Table S3 in SD [28][29][30][31][32][33]. To estimate the detection limit of Ag NCs on ZnO ND system, an optimized ND 2b was used for the detection of CV molecules at low concentrations.…”

Morphological evolution of gold nanoparticles on silicon nanowires and their plasmonics

“…11 Recently, heterostructures of onedimensional nanowires integrated with extraneous nanoparticles were demonstrated to be of great interest due to their excellent detection sensitivity, reproducibility, stability, and biocompatibility. 12,13 Silicon (Si) nanowires have been utilized in bioelectronics, nanoelectronics, optical devices, and energy devices. [14][15][16] The pristine Si nanowires only exhibit moderate Raman sensitivity for molecular detection, and thus proper surface modication or heterostructuring of the nanowires are of particular interest for the purpose of SERS sensing.…”