Preparation Of Nano Palladium And Platinum Composites For2,6-dichlorophenol And CO₂Sensing

Nanopalladium/β-cyclodextrin complex modified nickel steel electrode wasprepared for2,6-dichlorophenol （2,6-DCP） sensing. The processes involved threesteps: thiocholine was convently modified at the nickel steel electrode （Ni-Fe）using a cyclic voltammeter method （TCh/Ni-Fe）; β-cyclodextrin （β-CD） wasself-assembled at TCh/Ni-Fe by electrostatic attraction （β-CD/TCh/Ni-Fe）; then,nano-palladium was electrodeposited at β-CD/TCh/Ni-Fe to formPd/β-CD/TCh/Ni-Fe. The electrode was characterized by various methods includingfield emission scanning electron microscope （FE-SEM）, X-ray diffraction （XRD）,X-ray photoelectron spectroscopy （XPS） and electrochemical techniques. A like-earand equal distribution for nano-palladium could be observed with a size of17.2±4nm. The electrode showed an excellent electrocatalysis for the redox of2,6-DCP. Ithas been successfully applied to2,6-DCP sensing in a concentration range of1×10^-61×10^-4mol·L^-1[i （A）=2.8×10^-3+11.9Cx(mol·L^-1), R=0.996, detectionlimit:1×10^-9mol·L^-1（3σ）].Platinum nanoparticles were grafted on multi-walled carbon nanotubes usingultrasonic synthesis method （Pt/MWCNTs）. The catalyst was characterized by filedemission scanning electron microscope （FE-SEM）, X-ray diffraction （XRD） andelectrochemical techniques. The results showed that Pt nanoparticles werehomogeneously inlaid on the surfaces of MWCNTs with an average size of40±20nm. The catalyst showed an excellent eletrocatalysis effect towards the reduction ofcarbon dioxide （CO₂）, it was used as CO₂sensing, and two good linearrelationships were respectively obtained at Pt/MWCNTs modified glassey carbonelectrode from1×10^-61×10^-5mol·L^-1and1×10^-51×10^-4mol·L^-1with adetection limit of1×10^-6mol·L^-1.