Differential Pulse Anodic Stripping Voltammetry Research Articles

Development of pectin-based gel electrolyte for wireless electrochemical determination of cadmium and lead using smartphone

A portable device offering effortlessness, mobility, and affordability for real-time and on-site monitoring of heavy metals is currently in great demand to maintain environmental sustainability. Herein, a platform utilizing a biopolymeric gel-based electrolyte for the on-field simultaneous determination of Cd(II) and Pb(II) is described. Pectin, a natural polymer, was exploited as a chemical delivery medium on account of its biodegradability, environmental friendliness, and rapid dissolving characteristics. The gel electrolyte was prepared by having pectin dissolved in KCl mixed with Sb(III)–Bi(III) bimetallic alloy solution, and casted onto a paper substrate. An in situ bimetallic alloy and pre-mixed bismuth nanoparticles modified screen-printed graphene electrode (Sb–Bi/BiNP/SPGE) were employed to enhance the electrochemical signals of Cd(II) and Pb(II) for the differential pulse anodic stripping voltammetry (DPASV). It was demonstrated that the platform was capable of generating sharp and well-defined current signals, achieving the low detection limits of 50.98 ng mL−1 for Cd(II) and 40.80 ng mL−1 for Pb(II). The reproducibility, as indicated by the relative standard deviation, was found to be less than 10.4 % (n = 10) for the developed gel-based device when coupled with a wireless near field communication (NFC) potentiostat. Lastly, the obtained sensor was applied for quantification of Cd and Pb in potentially contaminated groundwater samples. The recoveries obtained were satisfactorily within the acceptable range. The newly designed platform exhibited several advantages, including small sample volume (μL), low-cost, no sample preparation requirements, and being environmentally friendly. The convenience of a portable device utilizing the proposed biopolymeric gel-based electrolyte for on-field analysis makes it highly appealing for various applications.

Electrochemical sensing of Pb2+, Cu2+, and Hg2+ by an aminoclay-based porous covalent organic polymer/ multi-walled carbon nanotubes modified glassy carbon electrode

We present a novel electrochemical sensor for the simultaneous detection of Lead (Pb2+), Copper (Cu2+), and Mercury (Hg2+) ions in seafood samples using differential pulse anodic stripping voltammetry (DPASV) technique. The sensor incorporates an aminoclay-based porous covalent organic polymer (AC-PCOP) derived from the polymerization of aminoclay and 1,3,5-benzenetricarboxylic acid (trimesic acid). To enhance conductivity, the AC-PCOP is combined with multi-walled carbon nanotubes (MWCNTs) and utilized for modifying the surface of the glassy carbon electrode (GCE). The AC-PCOP was characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, and infrared spectroscopy (IR). These analyses confirmed the presence of a hierarchical architecture in the AC-PCOP, which exhibited a spherical shape. The proposed modifier facilitates the deposition-stripping process and electron diffusion between electrolyte and heavy metal ions. Optimized conditions yielded limit of detections (LODs) of 0.0006, 0.0016, and 0.0003 nM, with linear ranges from 0.002 to 1000 nM, 0.005 to 1000 nM, and 0.001 to 1000 nM for Pb2+, Cu2+, and Hg2+, respectively. The sensor successfully measured these ions in seafood samples. Control experiments and validation were performed using cold vapor atomic absorption spectrometry (CVAAS) to determine the ions in the chosen food samples.

Adaptive Fabrication of Electrochemical Chips with a Paste-Dispensing 3D Printer.

Electrochemical (EC) detection is a powerful tool supporting simple, low-cost, and rapid analysis. Although screen printing is commonly used to mass fabricate disposable EC chips, its mask is relatively expensive. In this research, we demonstrated a method for fabricating three-electrode EC chips using 3D printing of relatively high-viscosity paste. The electrodes consisted of two layers, with carbon paste printed over silver/silver chloride paste, and the printed EC chips were baked at 70 °C for 1 h. Engineering challenges such as bulging of the tubing, clogging of the nozzle, dripping, and local accumulation of paste were solved by material selection for the tube and nozzle, and process optimization in 3D printing. The EC chips demonstrated good reversibility in redox reactions through cyclic voltammetry tests, and reliably detected heavy metal ions Pb(II) and Cd(II) in solutions using differential pulse anodic stripping voltammetry measurements. The results indicate that by optimizing the 3D printing of paste, EC chips can be obtained by maskless and flexible 3D printing techniques in lieu of screen printing.

Voltammetry determination of Cd(II) and Pb(II) at TiO2/reduced graphene oxide modified electrodes

AbstractIn this article, a TiO2/reduced graphene oxide (rGO) composite was synthesized from rGO and soluble titanium hydroxide‐peroxide complexes. The obtained materials were characterized by X‐ray diffraction, scanning electron microscopy, nitrogen adsorption/desorption, Raman spectroscopy and energy dispersive X‐ray spectroscopy‐elementary mapping. The TiO2/rGO composite was used as an electrode modifier for developing an electrochemical sensor to simultaneous analysis of Cd(II) and Pb(II) by using differential pulse anodic stripping voltammetry (DP‐ASV). Under optimal conditions, the linear correlation between the stripping peak current and the metal ion concentration is good in the range of 5–100 ppb for both metals (R2 ≥ 0.998), and a low detection limit (3.17 ppb for Cd(II) and 2.42 ppb for Pb(II)) was obtained. The interference study revealed that some metal cations had little influence on the DP‐ASV signals of Cd(II) and Pb(II). In addition, the developed electrode exhibited satisfied reproducibility and repeatability. The TiO2/rGO‐modified electrode was tested toward the detection of Cd(II) and Pb(II) in river waters and the obtained exceptional recoveries and results were further associated with AAS results. This study indicates that the TiO2/rGO composite might be an alternative for practical applications in the electrochemical determination of heavy metal ions in aquatic solutions.

Synthesis, properties, and applications of all-solid-state reference electrode based on AgTi2(PO4)3

High-density AgTi2(PO4)3 as a solid electrolyte was synthesised by a high-temperature solid-state process. The optimal sintering temperature was determined to obtain the best structural and electrical performance. Based on the as-prepared AgTi2(PO4)3 fast-ion conductor, a new type of all-solid-state reference electrode was prepared, and its electrochemical properties, such as cyclic voltammetry curves and potentials at varying pH, were investigated. A pH sensor was designed by combining an AgTi2(PO4)3 reference electrode with an Ir/IrO2 pH electrode. This pH sensor exhibited a good linear response to pH values in aqueous solutions and simulated seawater samples. In addition, a metal ion sensor, comprising the as-fabricated solid-state reference electrode, a Pt counter electrode, and a glassy carbon working electrode, was employed to quantify Cu2+, Hg2+, and Pb2+ concentrations using differential-pulse anodic stripping voltammetry. The resulting peak currents correlated with the metal ion concentrations and exhibited a low detection limit, good linearity, and wide detection range, which is suitable for performing chemical analysis in harsh marine environments.

Electrocatalytic detection of Hg(II) using a platinum electrode modified with composite film of cobalt(II) phthalocyanine tetra-substituted with 1-(methoxymethyl)-benzotriazole groups and co-electropolymerized polypyrrole

The presence of mercury adversely affects the daily lives of humankind due to its acute toxicity and environmental persistence. Therefore, the development of cost-effective smart materials which can allow the real time, ultrasensitive and discriminatory monitoring of mercury concentrations in industrial and municipal water treatment plants is an imperative. It is foreseen that this proposed water quality assurance measure will be of utmost importance to identify the culprits for the wide prevalence of this heavy metal ion in the environment. Herein, a platinum electrode (Pt) was modified via the simultaneous electropolymerization of polypyrrole (PPy) and the co-electrodeposition of tetra-[4-((1H-benzotriazole)methoxy)phthalocyaninato]cobalt(II) (CoPc-Bzt, 2, (Btz = benzotriazole)). The complementary electrode modification processes were performed in a 1:1 (v: v) DMF: acetonitrile containing 1 M tetrabutylammonium hexafluorophosphate electrolyte solution over 20 cycles using cyclic voltammetry to afford the chemically modified electrode (CME), Pt|PPy/2. Differential pulse anodic stripping voltammetry (DPASV) was used to detect Hg(II) ions using the CME within a 10 µM to 100 µM linear range while calculated limits of detection and quantification (LOD and LOQ) were determined as 3.11 and 10.00 µM, respectively. The analytical performance of the CME rendered a statistically accepted percentage recovery (97.4%) whereas that of Inductively Coupled Plasma – Optical Emission Spectroscopy (ICP-OES) is 112.3%.

Synthesis of AgNPs/MnO2/rGO composite materials with adsorption properties and their application in analysis of anti-inflammatory and antibiotic agents

In this article, AgNPs and MnO2 were successively synthesized on the Graphene oxide (GO) substrate using an in situ method. The AgNPs/MnO2/GO nanocomposite material was modified onto the surface of a glassy carbon electrode (GCE) and the material was electrochemically reduced on the electrode surface. The material obtained after reduction was called AgNPs/MnO2/rGO, which was confirmed by X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) to examine the chemical bonding and by scanning electron microscopy (SEM) combined with energy-dispersive spectroscopy (EDS) to demonstrate the elemental characteristics of the material. In addition, X-ray photoelectron spectroscopy (XPS) analysis was performed to determine the elemental composition, chemical state, and electronic state of the elements on the surface of the material. The application of the reduced material was for the analysis of Piroxicam and Ofloxacin using the differential pulse anodic stripping voltammetry (DP-ASV) method. The investigation of pH and scan rate (v) indicated that the synthesized material had adsorption properties and was applied for the analysis of the anti-inflammatory drug Piroxicam and the antibiotic Ofloxacin.

Heavy metal sensing in plant and soil solutions using carbon fiber electrode

Analysis of trace level metals in environmental samples (e.g., soil, water, and plant samples) is important for assessing environmental quality and food safety. This paper reports a non-toxic, eco-friendly, and cost-effective sensing method, capable of in-situ detection of microgram per liter (µg/L) levels of heavy metal ions in plant and soil solutions using carbon fiber electrodes (CFEs) produced without using any microfabrication. The electrochemical behaviors of the CFEs were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements. As proof of principle, the CFEs were validated for sensing selected heavy metals in buffer solutions as well as in extracted plant and soil solutions using differential pulse anodic stripping voltammetry (DP-ASV). Experimental results confirm that the CFEs were able to simultaneously measure cadmium (Cd), lead (Pb), and mercury (Hg) with a detection limit of 2.10, 0.93, and 1.85 µg/L respectively in buffer solution, showcasing good selectivity and sensitivity. The ideal pH range for heavy metal detection was also extensively investigated and was found to be between pH 4.0 and pH 5.0. These findings lay a better foundation towards long-term and stable electrochemical analysis for plant and soil solution matrices.

Didactic experiment for voltametric determination the complexing capacity of natural waters

The titration method can be applied to determine the complexation capacity between metal ions and ligands in natural water samples. The process involves the incremental addition of the metal to the sample containing a specific ligand, resulting in a titration curve that reflects the formation of complexes. The change in the curves slope indicates the saturation of the complexation capacity. In this study, the copper (II) ion was used due to its stability with organic ligands. The titration curve was analyzed to determine the complexation capacity (CC) and conditional formation constant (K) of the complex. Different mathematical treatments are proposed for this analysis. In the described experiment, differential pulse anodic stripping voltammetry was used to determine the complexation capacity of humic substances in natural waters. Experimental parameters such as pH, supporting electrolyte concentration, and volume of additions were previously optimized for the voltammetry technique. The obtained data were processed and analyzed, resulting in titration curves and voltammograms. The analysis of the curves allowed for the calculation of the complexation capacity and conditional stability constant of the formed complex. The results demonstrate the feasibility of the method as a didactic experiment for the voltammetric determination of natural water complexation capacity.

Simultaneous effect of pH, deposition time, deposition potential, and step potential on the stripping peak current of lead and cadmium by response surface methodology

In this paper, a simple voltammetric method has been reported for the lead, and cadmium determination using platinum nanoflowers modified glassy carbon electrode (PtNFs/GCE). The effects of pH, deposition time, deposition potential, step potential were investigated on the stripping peak current of lead, and cadmium based on response surface methodology (RSM). The results of RSM analysis and analysis of variance (ANOVA) have shown that the experimental data could be well described by quadratic regression equations with determination coefficients (R2) of 0.935, and 0.972 for the stripping peak current of lead, and cadmium, respectively. Results of the statistical analysis showed that the fit of the model was good in all cases. The maximum stripping peak current of the lead, and cadmium of 5.54µA, and 2.81µA, respectively were obtained at the optimum levels of process variables (pH (4.72), deposition potential (-1.14V), deposition time (120s), step potential (7mV)). Testing the model to analyze lead, and cadmium on the PtNFs/GC electrode using differential pulse anodic stripping voltammetry (DPASV) and obtained with the stripping peak current of the lead, and cadmium of 5.43µA, and 2.75 µA, respectively.

Simultaneous electrochemical sensing of heavy metal ions (Zn2+, Cd2+, Pb2+, and Hg2+) in food samples using a covalent organic framework/carbon black modified glassy carbon electrode

In this study, for the first time, a selective electrochemical sensor by glassy carbon electrode (GCE) modified with the covalent organic framework (COF) and carbon black (CB) was introduced and applied to simultaneous sensing of Zn2+, Cd2+, Pb2+, and Hg2+ via differential pulse anodic stripping voltammetry (DPASV). The COF is supplied through a condensation reaction between melamine and trimesic acid. The COF and CB, which are used to modify the GCE surface, increase electrochemical activity. The linearity to determine ions was achieved as Zn2+: 0.009–1100 nM, Cd2+: 0.005–1100 nM, Pb2+: 0.003–1100 nM, and Hg2+: 0.001–1100 nM. Besides, the detection limits for Zn2+, Cd2+, Pb2+, and Hg2+ have obtained 0.003, 0.002, 0.001 and 0.0003 nM, respectively. The CB-COF/GCE was applied to simultaneously measure the ions in food samples. For validation, atomic absorption spectrometry (AAS) was applied to measure the amount of target metal ions as a standard method in real samples.

Bismuth Nanoparticles Modified Indium Tin Oxide-Coated with Polyethene Terephthalate Electrode Using Hydrothermal Method for Pb Detection

Heavy metal elements are elements with comparatively high density and are dangerous even in a minimal quantity as they can persist in the environment. The electrochemical sensor can play an essential role in detecting heavy metals. However, the electrochemical sensor has drawbacks, such as low sensitivity and a high detection limit. Bismuth nanoparticles (BiNPs) can improve the sensitivity and lower the detection limit of an electrochemical sensor by modifying the working electrode. In this study, BiNPs produced by the hydrothermal method were drop-casted on the indium-tin-oxide (ITO) coated with polyethene terephthalate (PET) film (BiNPs/ITO-PET). The effect of the hydrothermal reaction was studied by varying the hydrothermal reaction period (5, 6, 7, and 8 h). X-ray Diffraction (XRD) was used to characterize the phase presence, and the morphology of BiNPs was characterized using a transmission electron microscope (TEM). The BiNPs/ITO-PET electrode was subjected to electrochemical characterization using cyclic voltammetry (CV) and the detection of Pb(II) using differential pulse anodic stripping voltammetry (DPASV). The BiNPs/ITO-PET electrode showed good electrochemical performance in detecting Pb(II).

An ultrasensitive electrochemical sensor for detecting Cd(II) in aquatic products based on CS/COFs/PEDOT: PSS modified acupuncture needle electrode

The use of low-cost working electrodes is of great importance for the development of sensor industrialization. Acupuncture needles electrode (ANE) was selected as working microelectrode, a sensor was designed based on poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT: PSS) and chitosan (CS) modified covalent organic frameworks (COFs) (CS/COFs) for detection of cadmium (Cd(II)). First, a mixture of PEDOT and PSS was electrodeposited on the surface of the acupuncture needles to synthesize a PEDOT: PSS as conductive polymeric film to support the electron transfer capability and enhance the conductive efficiency of the sensor. Then, CS/COFs was self-assembled and attached to the PEDOT: PSS/ANE surface by π-π stacking intermolecular interaction forces and the viscosity of CS, thus increasing the specific surface area of the electrode. Differential pulse anodic stripping voltammetry (DPASV) was used as the electrochemical method for detection of Cd(II). And the results indicated that the CS/COFs/PEDOT: PSS/ANE was linearly responsive in the range of 400 μg/L to 2400 μg/L, and the LOD was 13.8 ng/L for Cd(II). The constructed sensor also showed great selectivity, reproducibility, and stability. Additionally, the sensor demonstrated outstanding recovery in the detection of Cd(II) in real sample scallops. This sensing construction method based on acupuncture needles as working electrodes is of great significance to the development of sensor industrialization and aquatic product safety detection.

Simultaneous quantification of lead, cadmium and zinc in superficial marine sediments using a carbon-fiber microelectrode modified with bismuth film

Marine sediments are a useful environmental assessment matrix as they naturally trap toxic substances of anthropogenic origin and thus have higher concentrations of these than the surrounding water. Therefore, developing methods for the sensitive, accurate, and inexpensive quantification of these substances is important, as the traditional techniques have various disadvantages. The current study evaluated the effectiveness of an in situ bismuth-modified carbon-fiber microelectrode (voltamperometric sensor) to simultaneously detect Pb, Cd, and Zn in marine sediments from Puerto Jeli in El Oro Province, Ecuador. This site is representative of the contamination levels present along the coast in this province. Differential pulse anodic stripping voltammetry was applied, and the resulting linear regression for the metal quantification ranged from 12 to 50 μg mL−1, with quantification limits for Pb(II), Cd(II), and Zn(II) of 18.69, 12.55, and 19.29 μg mL−1, respectively. Thus, the quantification with the sensor was successful. According to the preliminary results, Cd and Pb values exceeded the permissible limits established by Ecuador (Texto Unificado de la Legislación Secundaria del Ministerio del Ambiente) and the US Environmental Protection Agency, respectively.

Engineered CoFe2O4@NiFe LDH nanocomposite based electrochemical sensor for the detection of Cr, As, Sb and Tl in various supporting electrolytes

The early detection and timeous monitoring of trace metals within the environment is crucial, especially with the need to develop mitigating strategies that help reduce health challenges. In this context, the electrochemical detection of Cr(VI), Sb(V), As(III), As(V) and Tl(III) has been performed using differential pulse anodic stripping voltammetry (DPASV) on a glassy carbon electrode modified with CoFe2O4@NiFe LDH. The anticipated active sites, such as the surface hydroxyl and oxide groups on the highly mesoporous nanoflower-like CoFe2O4@NiFe LDH composite that can readily interact with trace metal ions, were identified through physiochemical characterisation. The electrochemical characterisation revealed that the electrical conductivity was improved upon modifying the glassy carbon electrode with the CoFe2O4@NiFe LDH modifier. Subsequently, the developed sensor demonstrated a remarkable response on the detection of Cr(VI), Sb(V), As(III), As(V) and Tl(III), with good linearity (0.13–50 µg/L), low limit of detection (0.14, 0.15, 0.09, 0.12 and 0.19, respectively), low limit of quantification and high sensitivity. Significant parameters critical to the sensor's performance, such as type of electrolyte solution, deposition potential, deposition time and pH, were optimised. The DPASV results suggested that the developed sensor was repeatable and reproducible with intra-day and interday precision below 5 %. The proposed electrochemical sensor performed very well in tap and river water samples and could, therefore, open new avenues for the selective detection of trace metals in various matrices.

Nano-Needle Boron-Doped Diamond Film with High Electrochemical Performance of Detecting Lead Ions

Nano-needle boron-doped diamond (NNBDD) films increase their performance when used as electrodes in the determination of Pb2+. We develop a simple and economical route to produce NNBDD based on the investigation of the diamond growth mode and the ratio of diamond to non-diamond carbon without involving any templates. An enhancement in surface area is achievable for NNBDD film. The NNBDD electrodes are characterized through scanning electron microscopy, Raman spectroscopy, X-ray diffraction, cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse anodic stripping voltammetry (DPASV). Furthermore, we use a finite-element numerical method to research the prospects of tip-enhanced electric fields for sensitive detection at low Pb2+ concentrations. The NNBDD exhibits significant advantages and great electrical conductivity and is applied to detect trace Pb2+ through DPASV. Under pre-deposition accumulation conditions, a wide linear range from 1 to 80 µgL−1 is achieved. A superior detection limit of 0.32 µgL−1 is achieved for Pb2+, which indicates great potential for the sensitive detection of heavy metal ions.

NiFe2O4/G-C3N4 modified pencil graphite electrode for mercury(II) detection

The design and development of composite electrodes towards the trace-level detection of Hg(II) ions has triggered paramount importance in the area of electrochemistry. In this context, pencil graphite electrode was modified with NiFe2O4/G-C3N4, wherein bimetallic oxides were heterogeneously grown over the g-C3N4 sheets through a wet chemical approach. The results derived from transmission electron microscopy and X-ray diffraction analysis indeed reflected that NiFe2O4 were uniformly distributed over the sheet surface and complemented with effective interactions between them. The composites were coated over a pencil graphite electrode (PGE) and were used for the electrochemical detection of Hg(II) ions under various conditions. The cyclic voltammetry (CV) and differential pulse anodic stripping voltammetry (DPASV) reveal better electrochemical performance of modified electrodes compared to bare PGE, G-C3N4/PGE, and NiFe2O4/PGE. The improved charge transfer kinetics at the electrode-electrolyte interface were the dominant factor to exhibit higher performance. The proposed sensor showed acceptable reproducibility and stability under the optimal reaction conditions. Additionally, the sensor showed a broad linear range from 10 to 800 nM with a limit of detection (LOD) of 2.49 nM. Further, the fabricated sensor has been successfully employed to determine Hg(II) contents in real water sample matrices.

Integrating catalytic role of gold nanoparticles with in-situ confinement effect of zirconium-based metal-organic frameworks for electrochemical determination of methylmercury

Catalytic redox reactions and size matching effect between the target molecule and sensing material are reliable methods for highly efficient determination of heavy metal ions. In this work, the electrochemical determination of methylmercury (CH3Hg+) was carried out gold nanoparticles (AuNPs) incorporated into four zirconium-based metal organic frameworks (MOF) with different pore diameters, namely MOF-801, (University of Oslo) UiO-66, UiO-67, UiO-68. The work relates the role of dicarboxylic ligands of different lengths to the AuNPs load capacity and the adsorption and reduction of CH3Hg+. The voltammetric properties of CH3Hg+ at different modified electrodes were studied by differential pulse anodic stripping voltammetry (DPASV). It was found that the CH3Hg+ electrochemical behavior was greatly influenced by the pore confinement effect of MOFs. Under the optimal conditions, the pore sizes of Au/UiO-67 are matched to CH3Hg+ molecule and they showed the highest response current. The possible reduction process of CH3Hg+ at the sensitive interface was explored by X-ray photoelectron spectroscopy (XPS) and chronoamperometry (CA). These four Au/MOFs modified GCE can also be used in detection of CH3Hg+ spiked in river water, confirming their potential application in the rapid detection of methylmercury in environmental samples.

Electrochemical Estimation of Cd and Cu Ions Simultaneously Using a Modified MgO/Fe2O3 Nanocomposite/Carbon Paste Electrode

Heavy metals are serious inorganic pollutants that need to be monitored in the hydrosphere with simple and cheap methods. Herein, a new sensor was fabricated by modifying a carbon paste electrode with MgO/Fe2O3 nanocomposite for simple, rapid, accurate, and highly sensitive simultaneous determination of Cd (II) and Cu (II) using differential pulse anodic stripping voltammetry. The electrochemical behavior of the constructed sensor was examined, and all parameters were optimized including deposition potential, time, pH, and scan rate. For Cd (II) and Cu (II), the respective detection limits were determined to be 3.3 × 10−11 M and 3.6 × 10−11 M, and the respective quantification limits were 1.1 × 10−10 M and 1.2 × 10−10 M. The sensor estimated Cd (II) and Cu (II) in Nile river, tap, and bottled real water samples with high recoveries ranging from 99 to 117%.Graphical

Electrochemical determination of mercury ions in different food samples using glassy carbon electrode modified with poly (crocin)

In this study, a glassy carbon electrode (GCE) modified with poly (crocin) (GCE/PCro) was designed for Hg2+ detection through the differential pulse anodic stripping voltammetry (DPASV) technique as a novel electrochemical sensor. Herein, differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and field emission-scanning electron microscopy (FE-SEM) were carried out to characterize the electrodes. Under optimal conditions, the linear range for Hg2+ was obtained at 0.1 to 300 pM and 300 to 2000 pM and, also, the limit of detection (LOD) (S/N = 3) was achieved at 0.033 pM. The prepared sensor was found to exhibit the qualities of selectivity, stability, repeatability, and reproducibility ability. To demonstrate the introduced sensor ability for real application, the modified electrode was employed to measure Hg2+ in tea, shrimp, and fish samples with a good recovery ranging from 98.50 to 103.02 – depicting that the modified electrode possesses satisfactory practicability to detect Hg2+.