Nickel tungstate nanoparticles: synthesis, characterization and electrochemical sensing of mercury(II) ions

Nano particulate metal oxides gained significant research interest in recent years for various applications with the intension of exploring enhanced properties of miniaturization. In this research work, nickel tungstate nanoparticles (NiWO4 nanoparticles) were successfully synthesized via a simple and efficient sucrose-nitrate decomposition method. The synthesized nanoparticles were characterized using various analytical techniques such as PXRD, SEM, TEM, BET measurements and FTIR. Transmission electron microscope images reveals the nearly spherical shaped nanoparticles of average particle size 15-35nm. Photoluminescence characteristics of synthesized NiWO4 nanoparticles were investigated at room temperature. Further, the prepared nanoparticles were utilized as glassy carbon electrode modifier for trace level electrochemical sensing of toxic mercury present in water samples. The electrochemical behavior of mercury(II) ions at modified electrode interface has been studied by cyclic voltammetry (CV) and differential pulse stripping voltammetry (DPSV). The results illustrate that, the proposed modified GCE sensor exhibits linearity between the concentration range 10-600nM with the limit of detection 2.25nM based on 3 sigma method for mercury(II) ions.