A Green, Rapid and Efficient Dual-Sensors for Highly Selective and Sensitive Detection of Cation (Hg2+) and Anion (S2−) Ions Based on CMS/AgNPs Composites

Abstract

Detection of mercury (Hg2+) and sulfide (S2−), universal and well-known toxic ions, is crucial in monitoring several diseases. How to design and fabricate the high-performance sensor for simultaneously and accurately detecting the Hg2+ and S2− is critical. Herein, we proposed a novel and convenient strategy for optical detection of Hg2+ and S2− by employing a carboxymethyl cellulose sodium/silver nanoparticle (CMS/AgNPs) colloidal solution, in which AgNPs were used as monitor for Hg2+ and S2−, and the CMS was utilized as both the stabilizer and the hydrophilic substrate for AgNPs. Well-identifiable peaks for Hg2+ and S2– were obtained in water based on UV–VIS absorption spectra, the absorbance intensity and/or position of nano-silver vary with the addition of Hg2+ cation and S2– anion, accompanying with color change. Impressively, the optimal AgNPs anchored CMS exhibited a high sensitivity and selectivity toward Hg2+ and S2−, the change in absorbance was linear with the concentration of Hg2+ (0–50 μM) and S2− (15–70 μM), and the lowest limits of detection (LOD) were 1.8 × 10−8 M and 2.4 × 10−7 M, respectively. More importantly, owing to the superior properties in testing Hg2+ and S2−, the fabricated sensor was successfully applied for detection of target ions in lake and tap water samples. All these good results implied that the designed strategy and as-designed samples is promising in detecting cation (Hg2+) and anion (S2−) ions and open up new opportunities for selecting other kinds of ions.

Silver Nanoparticles as Colorimetric Sensors for Water Pollutants

“…The nanospheres, highly symmetrical particles, are the most studied because of their monodispersity and synthetic reproducibility, that assure the repeatability of experiments and results. Spherical AgNPs and their composites have a widely application range, mostly in biotechnology and sensors [79][80][81]85,95,96]. The AgNPs show a typical localized surface plasmon resonance (LSPR) whereby the electrons on the AgNPs surface interact with electromagnetic radiation, generating LSPR and producing extinction and scattering spectra, with absorption bands in the 370-470 nm range.…”

“…On the other hand, the void area has been used to tune the refractive index, increase the active region for catalysis, and advance the ability to tolerate cyclic volume modifications. The morphology plays a key role, especially for the possibility of having materials with different symmetries (spheres, AgNPs, cubes AgNCs) [79][80][81][82][83][84][85][86][87] or without defined and reproducible symmetry (stars, AgNSs, flower, AgNFs, wires, AgNWs) [69,[88][89][90][91][92][93][94]. TEM images of silver nanoparticles of different geometries and shape are presented in Figure 4.…”

Preparation of Silver Nanoparticles in a Plasma-Liquid System in the Presence of PVA: Antimicrobial, Catalytic, and Sensing Properties

“…ere is evidence of the detection of metal ions using spherical silver nanoparticles. e use of silver nanoparticles for determination of Hg has been described [33]. In most cases, the determination is based on the formation of ionic and/or coordination bonds between metal ions and nanoparticle modifiers; therefore, the type of modifier plays an important role in regulating the sensitivity and selectivity of the determination.…”

Removal of Sulfide Ions from Kraft Washing Effluents by Photocatalysis with N and Fe Codoped Carbon Dots

“…In the kraft pulping of non-woody biomass, the extraction percentage of black liquor is usually lower than 80% [ 6 ], which means 20% of the spent chemicals enter the subsequent units. Sulfide ions (S 2− , or HS − under alkaline pH) are one of the major hazardous chemicals in kraft washing effluents (KWE) [ 7 ]. They impact the ETS by declining the performance of activated sludge due to their high oxygen demand and strong biological toxicity [ 8 ].…”