Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Tetrasulfide‐Functionalized Mesoporous Silica on Nanowire Ring Resonators for Detection of Aqueous Lead, Pb(II)

Tetrasulfide‐Functionalized Mesoporous Silica on Nanowire Ring Resonators for Detection of... Silicon‐on‐insulator (SOI) microring resonators coated with tetrasulfide‐functionalized mesoporous silica (MPS) (S4‐MPS) are reported as sensors to detect Pb(II) ions in aqueous solutions from 10 ppb to 1 ppm. The sensors are based on the interaction of the evanescent field of the guided light with the functionalized mesoporous silica films. Upon absorption of metal ions, the resonant wavelengths of the microresonators shift due to the increased refractive index of the film. The sensors are exposed to aqueous solutions of Pb(II) ions at different concentrations and time‐resolved absorption–desorption curves are obtained. The concentrations of Pb(II) ions are determined using the Lorentz–Lorenz model. It is found that two distinct binding sites with different affinities for Pb(II) are present in the S4‐MPS silica films, corresponding to tetrasulfide groups and, likely, silanol groups. The number of available binding sites corresponds to 1/25 of the total number of S4‐groups. Equilibrium constants for absorption of Pb(II) to both binding sites are obtained from the rate constants for the absorption and desorption processes. The initial absorption rates depend linearly on the concentration of Pb(II) and are used to determine the 3σ limit of detection as 58 ppbm in deionized water and 350 ppbm in tap water. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Advanced Sustainable Systems Wiley

Tetrasulfide‐Functionalized Mesoporous Silica on Nanowire Ring Resonators for Detection of Aqueous Lead, Pb(II)

Loading next page...
 
/lp/wiley/tetrasulfide-functionalized-mesoporous-silica-on-nanowire-ring-NQw860s8Ml

References (60)

Publisher
Wiley
Copyright
© 2019 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
eISSN
2366-7486
DOI
10.1002/adsu.201800084
Publisher site
See Article on Publisher Site

Abstract

Silicon‐on‐insulator (SOI) microring resonators coated with tetrasulfide‐functionalized mesoporous silica (MPS) (S4‐MPS) are reported as sensors to detect Pb(II) ions in aqueous solutions from 10 ppb to 1 ppm. The sensors are based on the interaction of the evanescent field of the guided light with the functionalized mesoporous silica films. Upon absorption of metal ions, the resonant wavelengths of the microresonators shift due to the increased refractive index of the film. The sensors are exposed to aqueous solutions of Pb(II) ions at different concentrations and time‐resolved absorption–desorption curves are obtained. The concentrations of Pb(II) ions are determined using the Lorentz–Lorenz model. It is found that two distinct binding sites with different affinities for Pb(II) are present in the S4‐MPS silica films, corresponding to tetrasulfide groups and, likely, silanol groups. The number of available binding sites corresponds to 1/25 of the total number of S4‐groups. Equilibrium constants for absorption of Pb(II) to both binding sites are obtained from the rate constants for the absorption and desorption processes. The initial absorption rates depend linearly on the concentration of Pb(II) and are used to determine the 3σ limit of detection as 58 ppbm in deionized water and 350 ppbm in tap water.

Journal

Advanced Sustainable SystemsWiley

Published: Jan 1, 2019

Keywords: ; ; ; ; ; ;

There are no references for this article.