Preparation Of Gold Nanostructures Based On Electrodeposition Technique And Its Application In Surface Enhanced Raman Spectroscopy And Glucose Sensing

Surface-Enhanced Raman Scatteirng (SERS) technique has been proven to be apowerful tool in obtaining vibrational information about molecules on or near ananoscale metallic surface and it has been a potential technique for non-destructive,sensitive detection of chemical and biological molecules. The noble metalnanoparticles (Ag，Au and Pt) have the property to produce high localized SurfacePlasmon Resonance (LSPR) effect. They have attracted attention from scientists.There are promisingly potential applications in field of electron, photon, bio-sensorand SERS. Au nanoparticles have relatively higher LSPR effect than other metals.Nevertheless they have stronger biocompatibility than that of other metals. Therefore,they can broaden the range of applications to biological fields, such as medicinerelease, biological imaging，and medical disputes, etc. There are numerous studies onthe fabrication of noble metal nanostructures as SERS active substrates. Fixing metalnanoparticles on the surface of solid substrate plays an important role in vairous fieldsof applications, for example, the fuel cell anode material, surface-enhanced Ramansubstrate and biosensor, etc. The current preparation methods include physical andchemical methods. The physical protocols contain nanosphere lithography coupled toiflm over nanospheres (NSL-FON), electron-beam lithography (EBL)，sputtering andelectrodeposition techniques, etc. The chemical methods include self-assembly andlayer-by-layer (LBL) technology. Utilizing electrochemical deposition to fabircatemetallic nanostructures is attractive for its versatility, facility, low cost, facile andsimple preparation, and easy accessibility. Several strategies have been proposed tofabricate metallic nanoparticles on conductive substrates, such as utilization of atemplate，or employing double potential pulses, or employing a cyclic voltammetryscan.This work demonstrates an economical, feasible yet robust method forelectrochemical deposition gold nanoparticles on indium tin oxide glass as SERSactive structure. To adjust the gold crystallographic orientation as SERS active substrate has been realized. This method will have profound inlfuence on the catalysis,control of crystallographic orientation and SERS substrate fabrication, etc. Quantumchemistry and computer technology are integrate to produce a new chemistry subject”computational chemistry". Development of computational chemistry provides theconditions to computation of chemistry systems. Density functional theory (DFT) is amulti-electron quantum mechanics study of tl e electronic systems. It has become animportant method for multi-particle theory-based research. It simplifies many-electronsystems to a single-electron system and it has faster calculation speed and calculationaccuracy. p-Aminothiophenol (p’ATP) and p-mercaptobenzoic (p-MBA) areimportant surface probes molecules in the Surface-Enhanced Raman Spectroscopy(SERS), both of them had a thiol group at the para position of aniline or carboxylgroup not only self-assembled monolayers (SAM) on metal surfaces but alsoexhibited very unique and strong surface-enhanced Raman signals. They had beenserved as the probe molecules and the as-prepared electrode exhibited good SERSperformance which would be a SERS analytical platform. Nevertheless, thetheoretical studies of the molecular adsorption on Au(l1l)-like nanoparticle array hadbeen carried out by density functional theory.Electrocatalytic glucose oxidation is an important research topic in several fields,such as employing glucose in ecologically firendly bio-ifiel cells for next generationenergy source and sensing glucose in blood for medical applications and in foodindustry. The development of sensing devices for the fast and reliable monitoring ofglucose and the carbohydrates for the treatment and control of diabetes has been afocal subject in analytical chemistry for the past decades. Yeager and Taniguchi haveundertaken some important study relevant to the Au-based nonenzymatic glucosesensors.In this work, Au(l ll)-]ike nanoparticle array was electrodeposited by novelelectrochemical protocol. This approach was feasible, controllable, cost-effective, andwithout any template or surfactant. The electrochemical behavior of oxidation ofglucose in alkaline media on the as-prepared electrode was discussed. In addition，the as-prepared electrode was served as an enzyme-free glucose sensor to detect theconcentration of glucose.