Influence Of Ag/SiO₂Nano-materials On Infrared Absorption And Raman Spectroscopy Of The Seawater Nutrients

Nutrient is one functional element in the ocean which has a close relationship with the biological process. In Oceanographic, traditional terms of nutrient elements of nitrogen, phosphorus, Silicon is one of the three primary elements. Undoubtedly nutrient plays an important role in the growth of marine organisms, however anomalous distribution of nutrients can also cause enormous stimulus on its growth. The seagrass eruption in Qingdao during the Beijing Olympic Games was the result of unusual content of the seawater nutrients. Rapid detection of the nutrients in the ocean becomes a pressing issue. This article researches the detection of nutrients in ocean exploration with surface-enhanced infrared/Raman Spectroscopy (SEIRAS: Surface-enhanced Infrared Absorption Spectroscopy; SERS:Surface-enhanced Raman Spectroscopy).In this article we prepare three silver/silica nano-composites with different silver content by the silver-mirror reaction. All these samples were characteristic with scanning electron microscope (SEM), x-ray diffraction (XRD), UV-visible absorption spectrum, infrared absorption spectroscopy to depict their surface morphology, structure of the sample characterization, optical characteristics. Results show that the nano silver particles, silicon dioxides have good uniformity in size and silicon dioxides are surround ed by nano-silver particles in different degree, but also silver/silica composites has the possibility of surface plasmon resonance in infra-red region.This article researches the infrared absorption spectrometry of nitrate in its evaporation process. Results indicate that the vibration modes of nitrate change with nitrate concentration, the half width, central wavenumber has changed in different degree. As the evaporation process, anti-symmetric stretch vibration of two nitrate absorption peak of the vibration mode integrals corresponding increase in area, all of reflecting composite films on nitrate anti-symmetric stretching vibration effects. We further study the effect of seawater salinity and the humic acid on infrared absorption spectrum properties of sodium nitrite and found that with the increase of salinity, the absorption peak integral area is gradually reduced. In this article, we also measured the infrared spectrometry of sodium phosphate and found that the Ag/SiO2composite material had strong enhanced function on its Raman spectrometry. The half band width and its peak integration area appear large change, while the central peak has no change. The infrared activity of sodium phosphate is weak, so the infrared spectra of is weak too.Results show that the aqueous silver/silica Nanocomposites in the different modes of vibration influence mainly from the silver nitrate/silica interface of hydration and nutrients, not much unlike that plasmon resonance.