Rapid selective analysis of arsenic and antimony using a novel Au-Fe3O4-C electrode sensor

Arsenic (As) and antimony (Sb) are emerging pollutants with significant toxicity and carcinogenic potential. Their contamination in drinking water represents a health and safety risk. A novel Au-Fe 3 O 4 -C sensor was synthesized using an electrodeposition technique that leverages the superior electro-catalytic properties of gold (Au), the high adsorption capacity of Fe 3 O 4 , and the excellent conductivity of carbon fiber cloth. The Au-Fe 3 O 4 -C sensor enhanced the sensitivity of As and Sb stripping signals and reduced the limits of detection. Square wave voltammetry (SWV), used for As analysis, yielding LODs of 0.24 μg L −1 for As(III) and 1.20 μg L −1 for As(V). Differential pulse voltammetry (DPV), used for Sb analysis, yielding LODs of 0.50 μg L −1 for Sb(III) and 0.60 μg L −1 for Sb(V). We report quantitative detection of As and Sb in a mixed solution through DPV combined with the non-linear least squares based on Pearson function. The portable electrochemical workstation combined with Au-Fe 3 O 4 -C sensor was installed on a mobile inspection vehicle to detect As/Sb in groundwater (Shanxi, China) and rivers (Hunan, China). The indication error reached below12%, confirming the capability of electrochemistry based on Au-Fe 3 O 4 -C sensor for the field determination.