Electrocatalytic Detection Of Formaldehyde On Nano Metal Modified Electrodes

Formaldehyde is a main kind of pollutant in room environment and damages people's health seriously. With the improvement of people's living standard, the detection of formaldehyde has been paid much attention. On the other hand, with the development and application of nanotechnology, the electrochemistry activity of formaldehyde on nanomaterial modified electrodes has received extensive interests.In this work, we prepared a new platinum nanoparticles modified glassy carbon electrode with an electrodeposition method. The results of scanning electron microscope and X-ray photoelectron spectroscopy indicated that we could modify a lot of spherical platinum nanoparticles on glassy carbon electrodes successfully with this method. The diameter of these spherical nanoparticles was in the range of 40~300nm. The nanoparticles deposited on glassy carbon electrodes were platinum without impurity.This kind of platinum nanoparticles modified glassy carbon electrode had a better catalytic effect on the oxidation of formaldehyde than common bulk platinum electrode. The electrochemical determination of formaldehyde was performed in 0.5M H2SO4 solution. In the range of 50 mg/L to 500mg/L,the peak current was linearly proportional to the concentration of formaldehyde. The detection limit was estimated to be 30mg/L.Meanwhile, we found that the electrochemical determination of formaldehyde on platinum nanoparticles modified electrodes could also be performed in the neuter buffer solution composed of Na2HPO4 and citric acid. In the range of 50 mg/L to 500mg/L,the peak current was linearly proportional to the concentration of formaldehyde. The detection limit was estimated to be 33mg/L.On the other hand, we prepared a novel gold nanoparticles modified glassy carbon electrode with the seed mediated growth method. This kind of modified electrode had a better catalytic effect on the oxidation of formaldehyde than common bulk gold electrode. The electrochemical determination of formaldehyde was performed in 0.1M NaOH (pH=13) solution . In the range of 5 mg/L to 100mg/L, the peak current was linearly proportional to the concentration of formaldehyde. The detection limit was estimated to be 1.9 mg/L.