Multi-mode Ion Sensing Based On Gold/Platinum Noble Metal Nanomaterials

Due to the advantages of both noble metals and nanomaterials,noble metal nanomaterials have unique physical and chemical properties.Therefore,noble metal nanomaterials have attracted great attention in the fields of physical,energy,catalysis,biomedicine,environmental governance and analytical sensing.With the increase of the kinds of noble metal nanomaterials,the analysis technology based on noble metal nanomaterials is developing and expanding gradually.However,due to the complex material preparation process and the complicated testing procedures,the simplicity and practicability of these methods are limited.Therefore,new materials or strategies are needed to develop simpler and more practical methods to expand the practical application of noble metal nanomaterials in the field of analytical sensing.In this paper,the Au-Cu core-shell nanocubes with uniform morphology and size and Pt-CTAB complexes were successfully prepared by simple methods,and successfully applied to the simple and accurate sensing research of Fe³⁺and I^-.This thesis mainly includes the following several aspects:1.First,the classification,synthesis and developing process of noble metal nanomaterials were introduced.Then,the applications of noble metal nanomaterials in the analysis of anions,heavy metal ions and small biomolecules were briefly reviewed.2.The monodisperse Au nanocubes were simply prepared by the hydrothermal method.Then,Au-Cu core-shell nanoprobe with uniform morphology and size was prepared by reducing copper ions to the surface of Au nanocubes with ascorbic acid（AA）as a reducing agent.Under acidic conditions,Fe³⁺can selectively etching the Cu shell in the material,and react with potassium ferricyanide in the base solution to produce prussian blue nanoparticles.The prussian blue nanoparticles not only have an obvious color change,but also a good photothermal effect.Therefore,based on the Fe³⁺-enabled in situ PB NPs generation-based reaction system,we successfully developed the sensitive photothermal and colorimetric dual-mode platform to detect the Fe³⁺in environmental samples.This dual-mode platform shows an obvious advantage in the field of POCT and instrument-free analysis of Fe³⁺in environmental samples,only using color and temperature as simple signal readout.3.Pt-CTAB complexes were prepared by simply mixing chloroplatinic acid（H₂PtCl₆）and cetyltrimethylammonium bromide（CTAB）.Under acidic conditions,I^-can effectively regulate the oxidation activity of Pt-CTAB complexes,and oxidize colorless TMB to a blue oxidation state TMB（oxTMB）in a short time.When TMB was oxidized to oxTMB,a variety of signals such as colorimetric,fluorescence,photothermal and electrochemical can be achieved.Therefore,based on the strategy of I^-regulated oxidation activity of Pt-CTAB complexes,we successfully constructed a multi-mode sensing platform for the detection of I^-.This sensing platform is not only more convenient and simple in terms of manufacturing and sensing,but also can be used in both laboratory testing and POCT.Therefore,this sensor platform has a broad application prospect.