Exploring the Modulation Mechanism of LSPR Effect of Cu Periodic Nanosphere Arrays to Promote the Performance of TiO2 Photoelectrode

Based on the previous exploration of the localized surface plasmon resonance (LSPR) effect of isolated Cu nanospheres to enhance the photoelectrochemical performance of TiO2 photoelectrode, this work further arranged Cu...

High-Sensitive Numerical Gas Detection Using LSPR Effect and Fano Resonance in a Slotted MDM Structure

A high-sensitive numerical measurement of methane based on the combined use of the localized surface plasmon resonance (LSPR) and Fano resonance in a slotted metal-dielectric-metal (MDM) periodic structure is numerically investigated. A groove is etched in an original MDM structure to excite the diploe mode at both sides of the groove, and the coherent coupling of two dipole modes is enhanced to realize a fast response, which is beneficial to gas-sensing. The influence of geometric parameters on the reflection spectra and methane sensitivity are analyzed to obtain optimal geometry. Moreover, an etching ring is introduced on the top metal to further raise the coupling area and coupling strength. The Fano resonance is subtly integrated into the optimized structure with asymmetry to achieve greater gas sensitivity. After the introduction of the Fano resonance, the field enhancement caused by the LSPR effect becomes greater and the methane sensitivity can reach up to 8.421 nm/% in numerical calculations, which increases 56.8% more than that of the original one. The combined use of the LSPR and Fano resonance in an optimized MDM structure provides an effective method for high-sensitive gas detection.

Real time detection of milk’s spoilage using Au/GO bend SMF sensor based on localized surface plasmon resonance effect

Potential of hybrid gold nanoparticles/Graphene Oxide (Au/GO) coated single mode fiber (SMF) sensor by exploiting localized surface plasmon resonance (LSPR) effect for detection of spoiled milk is studied. Various diameters of SMF’s cladding are prepared ranging from its original size, d=0.1250mm to d=0.1215mm. A mechanical polishing technique using sandpaper is applied to etch the cladding area in which results the SMF with diameter less than 0.1250mm. Hybrid layers of Au/GO are deposited onto the SMF via drop-casting technique by varies the number of layers of GO between one to five layers, meanwhile Au nanoparticles are kept constant at one layer. To generate LSPR, light with excitation wavelength of 1310nm and 1550nm are transmitted at the first end of Au/GO coated SMF resulting in strong scattering and extinction spectra. The fiber is bend about 8cm in diameter to produce evanescent waves around it. To investigate the sensitivity of sensor in detecting milk’s spoilage condition, the Au/GO bend SMF sensor is immersed into the milk’s solution which has been exposed to the environment for 24 hours, 48 hours and 72 hours. The maximum optical power response, ΔP%=6.85% is obtained when the one layer of Au/GO coated bend SMF had been immersed into the milk solution with exposure time of 24 hours. The values of ΔP% decrease about 3.50% and 2.00% respectively with the increment of exposure time at 48 hours and 72 hours. These results indicate the sensing ability of our proposed sensor to detect different levels of spoiled milk as the exposure time increased. The output of this study validates the main role of LSPR effect in enhancing the sensitivity of Au/GO bend SMF sensor for real time detection of milk’s spoilage.

Metallic tungsten carbide nanoparticles as a near-infrared-driven photocatalyst

In this study, we present the LSPR effect and full spectrum photoabsorption of metallic WC for the direct NIR-driven photoelectric conversion and photocatalytic degradation of organic pollutants.