Electrochemically Co-Deposition of Palladium Nanoparticles and Poly(1, 5-diaminonaphthalene) onto Multiwalled Carbon Nanotubes (MWCNTs) Modified Electrode and its Application for Amperometric Determination of Nitrite

摘要

In this article, palladium nanoparticles (PdNPs) and 1, 5- diaminonaphthalene (1, 5-DAN) wereelectrochemically co-deposited onto multiwalled carbon nanotubes (MWCNTs) modified glassy carbonelectrode (PdNPs-poly(1, 5-DAN)/MWCNTs/GCE). The morphology and properties of PdNPs-poly(1,5-DAN)/MWCNTs/GCE were characterized by scan electron microscope (SEM), energy dispersive X-ray spectrum (EDX) and electrochemical techniques. The proposed sensor exhibited an excellentelectrocatalytic performance for nitrite detection. The oxidation potential for nitrite detection at thefabricated sensors was decreased (0.792 V) and peak current was evidently improved, mainly due to thehigh synergistically catalytical effect of Pd nanostructures, poly(1, 5-DAN) and MWCNTs. The resultsrevealed that the electrooxidation mechanism of nitrite was involved two electrons transfer in theirreversible reaction at the PdNPs-poly(1, 5-DAN)/MWCNTs/GCE. The oxidation peak current of nitritewas proportional to its concentration with the linear range of 0.25 μM ~ 0.1 mM by amperometry, andthe limit of detection (LOD) was as low as 0.08 μM (S/N = 3). Furthermore, as-prepared sensors hadgood anti-fouling property, long-term stability and excellent practical ability, which was successfullyapplied to detect nitrite in real water samples and gained satisfactory recoveries of 97% ~ 105%.