Preparation Of Rhodium-doped Polystyrene@Silver Composite Structure Materials And The Studies Of Their Antioxidation Susceptibility

Silver nanomaterials are broadly defined as Silver material having at least one dimension in the three-dimensional space is in the range of 1¹00 nm or composed of them as basic units,having singular characteristics different from bulk materials such as large surface area and a large number of surface active sites.And this makes it have obvious unsaturated characteristics,and tend to spontaneous reunion,reduce the surface activity,thus greatly reducing its chemical activity and catalytic performance.In order to achieve the high surface activity and stability of silver nanoparticles and the characteristics of silver easily oxidized materials,the design and controllable synthesis of composite structure materials with specific properties have become the research direction of silver nanoparticles.In this paper,PS@Ag composite microspheres were prepared and studied,with controllable size,uniform particle size distribution,and uniform distribution of the polystyrene microspheres.And the oxidation resistance performance test was carried out on the basis of the study of the synthesis of materials,and the rhodium-doped PS@Ag composite microspheres with heterostructures.In order to improve the oxidation resistance of silver nanoparticles,rhodium-doped silver nanoparticles were prepared by hydrothermal method,the optimum preparation conditions by single factor experiment include hydrothermal reaction temperature of180?,hydrothermal reaction time of 5h,with 1.74g PVP,0.10mol/L AgNO₃,30.00mL NaHCO₃ and the rhodium/silver molar ratio of 3‰.When the rhodium/silver molar ratio varied from 1‰to 5‰,the shape of the silver nanoparticles was spherical,triangular,short rod and cubic,the same as those without the rhodium ions.The results of UV-vis absorption spectroscopy showed that rhodium could improve the oxidation resistance of silver nanoparticles obviously,and with the increase of rhodium/silver mole ratio,the oxidation resistance of silver nanoparticles to H₂O₂ was enhanced firstly,occurred the phenomenon of the red-shift of the peak before blue-shift.The polystyrene microspheres were successfully prepared by emulsion polymerization.The particle size and particle size distribution were continuously adjustable.The relationship between the amount of styrene,potassium persulfate,SDS,NaHCO₃,the volume ratio of ethanol to deionized water,and the particle size and size distribution of polystyrene microspheres were investigated by L₁₆?4⁵?orthogonal test.In order to further improve the activity of rhodium-doped silver nanoparticles,rhodium-doped PS@Ag composite microspheres were prepared by self-made polystyrene microspheres as core and chemical plating method.The relationship between the size of polystyrene microspheres as core,the amount of silver ammonia solution,the amount and order of PVP,the different rhodium/silver molar ratio,and the shape of silver nanoparticles as shell were investigated.The results of UV-vis absorption spectroscopy showed that when the concentration of hydrogen peroxide was less than 0.0005mol/L and the rhodium/silver molar ratio was 1‰,the antioxidation of PS@Ag composite microspheres was improved obviously.