Research On Catalytic Properties Of Platinum Nanomaterials And Their Application On Detection Of Heavy Metal Ions

Heavy metal ions pose a great harm to water bodies and the environment.It is necessary to develop sensitive and simple detection methods.Platinum nanomaterials have excellent peroxidase-like activity and catalytic chemiluminescence properties,and they can interact with heavy metal ions.Therefore,this project mainly focuses on the platinum nanomaterials,and compares the catalytic properties of different types of platinum nanomaterials and various platinum group metal nanometers.Based on this,the use of the interaction between heavy metal ions and platinum nanometers has been developed.The color method was used to detect both Ag⁺and Hg²⁺,and the method of chemiluminescence detection of Hg²⁺.The work of this topic mainly includes the following three aspects:1.Five platinum nanomaterials and gold-platinum core-shell nanoparticles with different particle sizes,different capping agents and different morphology were prepared.The capping agent involves PVP,sodium citrate and non-capping agents.The morphology includes spherical,porous,and cubic.The prepared nanoparticles were characterized by TEM,UV-Vis,and DLS analysis methods.2.The peroxidase-like catalytic activity of different nanomaterials was compared.The results showed that PVP-capped Pt NPs had the highest peroxidase activity.In combination with the inhibitory effect of Hg²⁺and Ag⁺on PVP-capped Pt NPs,EDTA was used as a masking agent to establish a colorimetric method for simultaneous detection of Hg²⁺and Ag⁺.The method showed a good linearity in the concentration range of 0¹00 nM.The detection limit of Ag⁺is 9.75 nM,R²=0.999,and the detection limit of Hg²⁺was 17.75 nM.In addition,the feasibility of this method for the determination of Hg²⁺and Ag⁺in tap water was also investigated.3.The catalytic chemiluminescence properties of different nanomaterials were compared.The results showed that PVP-capped Pt NPs had the most significant catalytic chemiluminescence effect.The mechanism of catalytic chemiluminescence catalyzed by PVP-capped Pt NPs,the influence of organic compounds and heavy metal ions on the luminescent system,and the mechanism of action were explored.Finally,using Hg²⁺to enhance the chemiluminescence properties of Pt NPs-Luminol,a chemiluminescence method for the detection of Hg²⁺was established.The method showed a good linear relationship in the concentration range of 0¹40 nM and 200¹000 nM,R² is 0.9968 and 0.9964 respectively.The detection limit is 8.62 nM.