Electrochemical determination of mercury in surface water samples using Au nanoparticles /electrochemically reduced graphene oxide modified electrode

• Published in: Materials research express 2025-01
• Main Authors: Trang, Ha Thuy, Anh Vu, Ho Xuan, Van Chung, Huynh Van Chung, Van Thanh, Ho, Duong, Hoang Ho Thuy, Hai Phong, Nguyen, Luyen, Nguyen Dinh, Khieu, Dinh Quang, Khac Lieu, Pham, Tuyen, Tran Ngoc
• Format: Article
• Language: English
• ISSN: 2053-1591; 2053-1591
• DOI: 10.1088/2053-1591/ada5c1

In the present work, we utilized Au nanoparticles /electrochemically reduced graphene oxide ( AuNPs/ErGO) as a modifier of glassy carbon electrode  to detect Hg(II) in surface water by a voltammetric method. The careful execution of the fabrication of AuNPs/ErGO on a glassy carbon electrode, achieved through the electrochemical reduction of graphene oxide (GO) and Au(III) solution using cyclic voltammetry, was a testament to our dedication and commitment. The modified electrode surface and the obtained materials were characterized by using a range of analytical techniques, including X-ray diffraction, Fourier Infrared spectroscopy, scanning electron microscopy, transmission electron microscopy,  energy-dispersive X-ray spectroscopy, elemental distribution maps, and electrochemical impedance spectroscopy. The results revealed the highly dispersed Au nanoparticles around 10-20 nm on the reduced graphene oxide matrix. Differential pulse-anodic stripping voltamtemtry (DP-ASV) was used for quantitative determinations, and the linear calibration curves were obtained in the Hg(II) concentration ranges of 2 to 15 ppb. The proposed DP-ASV approach offers a highly selective and sensitive method for Hg(II) determination with a limit of detection of 0.680 ppb. The study also meticulously addressed the common interfering species in aqueous solutions.  Finally, the modified electrode was applied to sensitively determine Hg(II) in tap, lake, and river water samples with satisfactory results.