The graphene-gold nanoparticles composite film modified glassy carbon electrode （EG- AuNPs/GCE） was prepared by one-step coelectrodeposition and employed for determination of trace mercury in environmental water wit...The graphene-gold nanoparticles composite film modified glassy carbon electrode （EG- AuNPs/GCE） was prepared by one-step coelectrodeposition and employed for determination of trace mercury in environmental water with differential pulse stripping voltammetry. Such a nanostructured composite film combined with the advantages of gold nanoparticles and graphene, can greatly promote the electron-transfer process and increase accumulation abil-ity for Hg（Ⅱ）, leading to a remarkably improved sensitivity. The linear calibration curve ranged from 0.2 μg/L to 30 μg/L for Hg（Ⅱ） and the detection limit （S/N=3） was found to be 0.03 μg/L at a deposition time of 300 s. Moreover, the stablity of the as-prepared electrode and interferences from other substances were evaluated. The modified electrode was successfully applied to the direct detection of Hg（Ⅱ） in real water samples.展开更多
Experimental investigations were conducted in this study to explore the effect of magnetization on water sample properties and to envisage whether the effect is beneficial for mercury detection in a sample of water or...Experimental investigations were conducted in this study to explore the effect of magnetization on water sample properties and to envisage whether the effect is beneficial for mercury detection in a sample of water or not. Subjecting the water sample to 0.3 Tesla magnetic field for 14 hours led to instantaneous effects on the examined water properties, where a reduction in the values of pH （7%） and interfacial tension （0.2%） was observed, whereas an increase （8%） in water electrical conductivity was recorded. Similar behaviours with slight changes in trend were observed after storing the samples for six days, which indicates a creation of permanent effects. Other experiments were conducted to explore the impact of magnetizing water sample containing inorganic mercury prior to detection by emission spectroscopy. Samples were prepared with different mercury concentrations and derivatized by using tin chloride （SnCI2）. The generated mercury vapour species were transported with aid of carrier gas into a dielectric barrier discharge plasma atomizer, in which the mercury signal at 253.65 nm was recorded. The results have shown 3.5%-7.5% increase in the signal intensities recorded for the magnetized samples, mostly attributed to a reduction in the sample surface tension and other reasons, which facilitates analyte derivatization.展开更多
文摘The graphene-gold nanoparticles composite film modified glassy carbon electrode （EG- AuNPs/GCE） was prepared by one-step coelectrodeposition and employed for determination of trace mercury in environmental water with differential pulse stripping voltammetry. Such a nanostructured composite film combined with the advantages of gold nanoparticles and graphene, can greatly promote the electron-transfer process and increase accumulation abil-ity for Hg（Ⅱ）, leading to a remarkably improved sensitivity. The linear calibration curve ranged from 0.2 μg/L to 30 μg/L for Hg（Ⅱ） and the detection limit （S/N=3） was found to be 0.03 μg/L at a deposition time of 300 s. Moreover, the stablity of the as-prepared electrode and interferences from other substances were evaluated. The modified electrode was successfully applied to the direct detection of Hg（Ⅱ） in real water samples.
文摘Experimental investigations were conducted in this study to explore the effect of magnetization on water sample properties and to envisage whether the effect is beneficial for mercury detection in a sample of water or not. Subjecting the water sample to 0.3 Tesla magnetic field for 14 hours led to instantaneous effects on the examined water properties, where a reduction in the values of pH （7%） and interfacial tension （0.2%） was observed, whereas an increase （8%） in water electrical conductivity was recorded. Similar behaviours with slight changes in trend were observed after storing the samples for six days, which indicates a creation of permanent effects. Other experiments were conducted to explore the impact of magnetizing water sample containing inorganic mercury prior to detection by emission spectroscopy. Samples were prepared with different mercury concentrations and derivatized by using tin chloride （SnCI2）. The generated mercury vapour species were transported with aid of carrier gas into a dielectric barrier discharge plasma atomizer, in which the mercury signal at 253.65 nm was recorded. The results have shown 3.5%-7.5% increase in the signal intensities recorded for the magnetized samples, mostly attributed to a reduction in the sample surface tension and other reasons, which facilitates analyte derivatization.
