Cold vapor integrated quartz crystal microbalance (CV-QCM) based detection of mercury ions with gold nanostructures

摘要: Abstract In this study, we developed a novel method of integrating the well-accepted cold vapor technique with gold nanostructured based quartz crystal microbalance (QCM) devices to selectively detect mercury ions (Hg2+). This allows for conversion aqueous into elemental (Hg°) form and thereon use highly sensitive QCM sensors evolved mercury. The involves reducing chloride (HgCl2) in contaminated water by mixing it 2% tin (SnCl2) solution order evolve Hg° from liquid mixture. selectivity sensitivity performance each nanostructure, namely, control Au thin film (Au-ctrl), Au-nanospheres (Au-NS) Au-nanourchins (Au-NU), towards was evaluated. It found that Au-NS Au-NU displayed up 79% 243% higher response magnitudes than Au-ctrl sensor various concentrations HgCl2, respectively. All three exhibited repeatable sensing when reporting 5 events involving 500 ppb HgCl2 Au-ctrl, having coefficient variance (CoV) values ˜5.7, 2.9 3.8%, Moreover, were observed operate linear region ion concentration range calibrated tested. Importantly, showed no cross-interference effects tested toward Hg2+ without presence other metal such as lead, cadmium, manganese, iron, zinc. results indicate CV-QCM is feasible be potentially used real-world monitoring applications.