Development of a novel setup for direct colorimetric visualization of elemental mercury vapor adsorption on colloidal gold nanoparticles

Mercury is a toxic، persistent، and bio-accumulative pollutant that has adverse effects on environmental and human health. Various studies have been conducted to monitor different forms of mercury. The objective of this study was to develop a novel setup for assessing gas phase elemental mercury vapor adsorption using colloidal gold nanoparticles solutions that display a characteristic surface plasmon resonance absorption peak in the visible spectrum. The UV-VIS-NIR spectrographs of gold nanoparticles blue shifts after exposure to mercury vapor. The surface plasmon resonances (SPR) of ∼4 and ∼30 nm gold nanoparticles were appeared with the sharp peaks at 515 and 528 nm respectively. The mercury vapor adsorbed in gold nanoparticles was related to the size. The amounts of mercury vapor adsorbed per grams of ∼4 and ∼30 nm gold nanoparticles solutions were obtained 1100 µg•g-1 and 1300 µg•g-1 respectively. A proposed novel setup based on UV-Vis spectroscopic undertaken to provide simplicity، use facilitating، potentially inexpensive، and sensitive enough is a suitable system for mercury vapor capture in many fields. It was demonstrated that the amount mercury adsorbed has been related to the sizes of gold nanoparticles. The color change was observed، when elemental mercury vapor adsorbed on the gold nanoparticles.