TY - JOUR
TI - A Ca2+ MOF combining highly efficient sorption and capability for
voltammetric determination of heavy metal ions in aqueous media
AU - Anastasia D. Pournara
AU - Antigoni Margariti
AU - Georgios D. Tarlas
AU - Andreas Kourtelaris
AU - Valeri Petkov
AU - Christos Kokkinos
AU - Anastasios Economou
AU - Giannis S. Papaefstathiou
AU - Manolis J. Manos
JO - Journal of Materials Chemistry A
PY - 2019
VL - 7
TODO - 25
SP - 15432--15443
PB - Royal Society of Chemistry (RSC)
SN - 2050-7488, 2050-7496
TODO - 10.1039/c9ta03337h
TODO - null
TODO - We recently discovered that a Ca2+ two-dimensional framework, namely
[Ca(H4L)(DMA)(2)]center dot 2DMA (Ca-MOF), was capable of exchanging
the Ca2+ ions with Cu2+ almost quantitatively in a matter of seconds in
aqueous solution. Herein, we report that Ca-MOF exhibits the capability
of both removal and voltammetric determination of heavy metal ions in
aqueous media. Ca-MOF shows one of the highest Pb2+ sorption capacities
(similar to 522 mg g(-1)) reported for MOFs. More importantly, a column
filled with Ca-MOF (1% wt) particles dispersed in silica sand (99% wt)
can quantitatively remove traces of Pb2+ (similar to 100 ppb) from a
relatively large volume of a wastewater simulant solution (containing a
large excess of competitive ions). Ca-MOF is also highly efficient for
sorption of Cd2+, Ni2+ and Zn2+, even in the presence of several
competitive cations. Actually, the Cd2+ sorption capacity (similar to
220 mg g(-1)) of Ca-MOF is one of the largest reported for MOFs.
Furthermore, detailed Ni2+ and Zn2+ sorption studies of MOFs have not
been described prior to this work. The mechanism of the M2+ (M2+ = Pb2+,
Cd2+, Ni2+, Zn2+) exchange process was elucidated based on a series of
spectroscopic, analytical and X-ray diffraction methods. In addition, a
simple ready-to-use electrochemical sensor based on modified graphite
paste with Ca-MOF was fabricated and successfully utilized for the
determination of Pb2+, Cd2+, Cu2+ and Zn2+ at mu g L-1 levels in aqueous
solutions by anodic stripping voltammetry (ASV). Overall, this work
demonstrates, for the first time, a dual function of a MOF as a sorbent
and as an electrochemical sensor for heavy metal ions, thus opening a
new window for materials with application in both environmental
remediation and monitoring.
ER -