The Electrical Response And Surface-enhanced Raman Scattering Of Au Nanopartical Arrays

Nanoparticle(NP)arrays with high sensitivity and enhancement factor are critical for the applications in flexible strain gauges,optoelectronic devices and photocatalysis.On the one hand,NP arrays could be used for the active units of strain sensor,of which the conductivity is sensitive the crevices between the particles.So far,a monolayer of spherical NPs actually exhibits anisotropic response to strain,which is crucial to improve the sensibility of flexible strain gauges.On the other hand,constructed sub-nm nanoscale gaps of Au NP chains is a new way to achieve the tremendous near-field coupling of localized surface plasmon resonance and improve the enhancement factor.Meanwhile,the electric field enhancement is closely related to the surface topography of NPs.Therefore,the electrical response of Au NP arrays and photocatalysis of Au NP chains were studied.The main content of this paper is as per following aspects:1.NP arrays and NP chains with sub-nm scale crevices were synthesized through the method of convective assembly,which were used as the active units of the flexible strain sensor and the SERS substrate separately.The coverage area of NPs chain could reach 15?m×15?m.2.Strain sensor made from a monolayer of urchin-like NPs onto a flexible substrate exhibited isotropic response to strain,of which the equivalent tunneling paths were randomly distributed on the substrate plane during external mechanical stimulus with different orientations.Through the design of this simple model,we researched the topography dependent isotropic tunneling in two dimensions NPs array.3.The SERS substrate of nanoparticle chain monolayer with tremendous near-field coupling could achieve the strong electric field enhancement of the NPs surface.we found that p-aminothiophenol(PATP)could be efficiently oxidized to4,40-dimercaptoazobenzene(DMAB).Secondly,when the power was 27.13?W,new Raman band at 1140,1388,and 1434 cm~-11 appeared in the SERS substrate of spherical NP chains.However,the conversion of PATP adsorbed on urchin-like NP chains to DMAB occurred at a lower power of 18.09?W.Thus,the catalytic performance of the urchin-like NP chains monolayer with sub-nm scale crevices was better than that of the spherical NP chains.