Passive Sampling of Gaseous Elemental Mercury Based on a Composite TiO2NP/AuNP Layer
Antonella Macagnano,
Paolo Papa,
Joshua Avossa,
Viviana Perri,
Marcello Marelli,
Francesca Sprovieri,
Emiliano Zampetti,
Fabrizio De Cesare,
Andrea Bearzotti,
Nicola Pirrone
Affiliations
Antonella Macagnano
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Research Area of Rome 1, Via Salaria km 29,300, 00016 Monterotondo, Italy
Paolo Papa
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Research Area of Rome 1, Via Salaria km 29,300, 00016 Monterotondo, Italy
Joshua Avossa
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Research Area of Rome 1, Via Salaria km 29,300, 00016 Monterotondo, Italy
Viviana Perri
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Research Area of Rome 1, Via Salaria km 29,300, 00016 Monterotondo, Italy
Marcello Marelli
Institute of Molecular Science and Technologies—National Research Council (ISTM-CNR), Via G. Fantoli 16/15, 20138 Milano, Italy
Francesca Sprovieri
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Division of Rende, c/o UNICAL-Polifunzionale, 87036 Arcavacata di Rende (CS), Italy
Emiliano Zampetti
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Research Area of Rome 1, Via Salaria km 29,300, 00016 Monterotondo, Italy
Fabrizio De Cesare
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Research Area of Rome 1, Via Salaria km 29,300, 00016 Monterotondo, Italy
Andrea Bearzotti
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Research Area of Rome 1, Via Salaria km 29,300, 00016 Monterotondo, Italy
Nicola Pirrone
Institute of Atmospheric Pollution Research—National Research Council (IIA-CNR), Division of Rende, c/o UNICAL-Polifunzionale, 87036 Arcavacata di Rende (CS), Italy
Passive sampling systems (PASs) are a low cost strategy to quantify Hg levels in air over both different environmental locations and time periods of few hours to weeks/months. For this reason, novel nanostructured materials have been designed and developed. They consist of an adsorbent layer made of titania nanoparticles (TiO2NPs, ≤25 nm diameter) finely decorated with gold nanoparticles. The TiO2NPs functionalization occurred for the photocatalytic properties of titania-anatase when UV-irradiated in an aqueous solution containing HAuCl4. The resulting nanostructured suspension was deposited by drop-casting on a thin quartz slices, dried and then incorporated into a common axial sampler to be investigated as a potential PAS device. The morphological characteristics of the sample were studied by High-Resolution Transmission Electron Microscopy, Atomic Force Microscopy, and Optical Microscopy. UV-Vis spectra showed a blue shift of the membrane when exposed to Hg0 vapors. The adsorbed mercury was thermally desorbed for a few minutes, and then quantified by a mercury vapor analyzer. Such a sampling system reported an efficiency of adsorption that was equal to ≈95%. Temperature and relative humidity only mildly affected the membrane performances. These structures seem to be promising candidates for mercury samplers, due to both the strong affinity of gold with Hg, and the wide adsorbing surface.
