title: Gold nanospikes based microsensor as a highly accurate mercury emission monitoring system.
abstract: Anthropogenic elemental mercury (Hg(0)) emission is a serious worldwide environmental problem due to the extreme toxicity of the heavy metal to humans, plants and wildlife. Development of an accurate and cheap microsensor based online monitoring system which can be integrated as part of Hg(0) removal and control processes in industry is still a major challenge. Here, we demonstrate that forming Au nanospike structures directly onto the electrodes of a quartz crystal microbalance (QCM) using a novel electrochemical route results in a self-regenerating, highly robust, stable, sensitive and selective Hg(0) vapor sensor. The data from a 127 day continuous test performed in the presence of volatile organic compounds and high humidity levels, showed that the sensor with an electrodeposted sensitive layer had 260% higher response magnitude, 3.4 times lower detection limit (~22 μg/m(3) or ~2.46 ppb(v)) and higher accuracy (98% Vs 35%) over a Au control based QCM (unmodified) when exposed to a Hg(0) vapor concentration of 10.55 mg/m(3) at 101°C. Statistical analysis of the long term data showed that the nano-engineered Hg(0) sorption sites on the developed Au nanospikes sensitive layer play a critical role in the enhanced sensitivity and selectivity of the developed sensor towards Hg(0) vapor.
authors.affiliation: Centre for Advanced Materials and Industrial Chemistry, School of Applied Sciences, RMIT University, GPO Box 2476V, Melbourne, VIC, Australia, 3001.
authors.forename: Ylias M
authors.initials: YM
authors.lastname: Sabri
authors.affiliation: Centre for Advanced Materials and Industrial Chemistry, School of Applied Sciences, RMIT University, GPO Box 2476V, Melbourne, VIC, Australia, 3001.
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Ippolito
authors.affiliation: Centre for Advanced Materials and Industrial Chemistry, School of Applied Sciences, RMIT University, GPO Box 2476V, Melbourne, VIC, Australia, 3001.
authors.forename: James
authors.initials: J
authors.lastname: Tardio
authors.affiliation: Centre for Advanced Materials and Industrial Chemistry, School of Applied Sciences, RMIT University, GPO Box 2476V, Melbourne, VIC, Australia, 3001.
authors.forename: Vipul
authors.initials: V
authors.lastname: Bansal
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, Australia.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: O'Mullane
authors.affiliation: Centre for Advanced Materials and Industrial Chemistry, School of Applied Sciences, RMIT University, GPO Box 2476V, Melbourne, VIC, Australia, 3001.
authors.forename: Suresh K
authors.initials: SK
authors.lastname: Bhargava
mesh_terms: D000818:Animals; D000835:Animals, Wild; D006046:Gold / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D008628:Mercury / Q000302:isolation & purification* / Q000633:toxicity; D053768:Metal Nanoparticles / Q000737:chemistry*
chemical_list: D006046:Gold; D008628:Mercury