Low cost, highly sensitive and selective electrochemical detection of arsenic (III) using silane grafted based nanocomposite

Abstract

Novel silane grafted bentonite was obtained using the natural bentonite as precursor material. The material which is termed as nanocomposite was characterized by the Fourier Transform Infra-red (FT-IR) and X-ray diffraction (XRD) methods. The surface imaging and elemental mapping was performed using Scanning Electron Microscopic (SEM/EDX) technique. The electroanalytical studies were performed using the nanocomposite electrode. The electroactive surface area of nanocomposite electrode was significantly increased than the pristine bentonite or bare carbon paste based working electrode. The impedance spectroscopic studies were conducted to simulate the equivalent circuit and Nyquist plots were drawn for the carbon paste electrode and nanocomposite electrodes. A single step oxidation/reduction process occurred for As(III) having ΔE value 0.36 V at pH 2.0. The anodic stripping voltammetry was performed for concentration dependence studies of As(III) (0.5 to 20.0 μg/L) and reasonably a good linear relationship was obtained. The detection limit of the As(III) detection was calculated as 0.00360±0.00002 μg/L having with observed relative standard deviations (RSD) less than 4%. The presence of several cations and anions has not affected the detection of As(III) however, the presence of Cu(II) and Mn(II) affected the detection of As(III). The selectivity of As(III) was achieved using the Tlawng river water sample spiked with As(III).

Facile Synthesized Novel Nanocomposites Modified Electrodes in the Trace Detection of Sulfamethoxazole

“…Similarly, the scissoring oscillations of an aliphatic chain of the organic silane are observed at 1473cm −1 -1481cm −1 . 49,51 Hence, these results confirmed that the organic silane (TC) is successfully grafted into the bentonite network and that the inclusion of Ag or Au nanoparticles does not cause marked changes in the IR peak patterns of the silane-modified TCBN composite.…”

Greener synthesis of novel nanocomposite material for efficient and selective trace detection of Pb²⁺: Insights of stability and real implications of fabricated electrode

“…These results inferred that pH 4.5 is an optimum pH for further electrochemical studies of Pb 2+ in aqueous medium. The other studies indicated that the detection of As 3+ is efficient at pH 2.0 using trichloro(octadecyl) silane grafted bentonite [48]. Deposition or the accumulation potential is a crucial parametric study in the stripping voltammetry since it significantly affects the sensitivity of the working electrode [2].…”

Electrochemical Detection of Arsenite Using a Silica Nanoparticles-Modified Screen-Printed Carbon Electrode

“…A further phenomenon worth noting is the range of pH in which the surface charge densities of amine-functionalized SiNPs influence the confrontation of As(III). The nanoparticles retain a net positive charge at pH values below 6.84 and carry a net negative charge at a higher pH (pH > 6.84) [35,36]. It is, therefore, predicted that negatively charged arsenite ions could be effectively migrated to the electrode surface under acidic conditions.…”