Novel solid-state sensor material for efficient cadmium(II) detection and capturing from wastewater

Abstract

Abstract In this study, the novel functional ligand was synthesized and then successfully immobilized onto the inorganic silica for the fabrication of solid-state sensor for simultaneous detection and adsorption of cadmium (Cd(II)) ion from water samples. The fabricated sensor was formed optical colour upon addition of trace amount of Cd(II) ion at experimental conditions. Several experimental parameters such as sensor morphology, solution pH, colour optimization, detection limit, competing ions effect, desorption and maximum adsorption capacity was evaluated. The data clarified that the materials could detect the ultra-trace level of Cd(II) ion according to the limit of detection was 0.88 µg/L based on the false positives and false negatives with the propagation of uncertainties. The solution pH was exhibited the key role, and the suitable pH 7.0 were selected based on the signal intensity and adsorption efficiency. The competing ions were not adversely affected in the Cd(II) ion detection and adsorption operation. In addition, the signal intensity was observed only for the Cd(II) ion, and these were clarified the high selectivity towards the Cd(II) ion at this experimental conditions. In addition, the adsorption data were well fitted with the Langmuir adsorption model with monolayer coverage. The determined maximum adsorption was 176.19 mg/g, which was comparable with the other forms of materials. The solid-state sensor was exhibited the high reusability based on the desorption performances. The desorption was carried out using 0.20 M HCl and then the sensor was ready to use after rinsing with water without significant loss in its performances. Therefore, the proposed solid-state sensor has high possibility in the real wastewater.