A Hydrogen Peroxide Sensor Based on Pt@Au Nanoparticles Loading to Polyethyleneimine Functionalized Carbon Nanotubes

A novel hydrogen peroxide sensor was fabricated by the seed-mediated growth method. Firstly, polyethyleneimine (PEI) functionalized multiwalled carbon nanotubes (MWNTs) were used as growth scaffold on a glass carbon electrode (GCE). Then, Au nanoparticles were uniformly electrodeposited as seeds. Finally, Pt nanoparticles (PtNPs) grew on Au PtNPs to form Pt@Au core-shell structure nanocomposite. A new type of electrochemical sensor based on Pt@Au/PEI-MWNTs nanocomposites for detection of hydrogen peroxide was then developed, and the designed Pt@Au/PEI-MWNTs/GCE was characterized by electrochemical methods and field emission scanning electron microscopy (FESEM). The differential pulse experiment results showed that the modified electrode exhibited excellent electrocatalytic activity towards the reduction of H 2 O 2 with the wide linear range from 9.2×10 −8 to 1.3×10 −3 M. The correlation coefficient was 0.9994 and the detection limit was down to 3.1×10 −8 M at the signal-to-noise ratio of 3.