RT info:eu-repo/semantics/article
T1 Nanoscale Au-In alloy-oxide core-shell  particles as electrocatalysts for efficient hydroquinone detection
A1 Medina Plaza, Cristina
A1 Rodríguez Méndez, María Luz
A1 Sutter, Peter
A1 Tong, Xiang
A1 Sutter, Elli
K1 Nanoparticle
K1 Sensor
AB The presence of hydroquinone (HQ), a phenolubiquitous in nature and widely used in industry, needs to bemonitored because of its toxicity to the environment. Here wedemonstrate efficient detection of HQ using simple, fast, andnoninvasive electrochemical measurements on indium tinoxide (ITO) electrodes modified with nanoparticles comprisingbimetallic Au−In cores and mixed Au−In oxide shells.Whereas bare ITO electrodes show very low activity for thedetection of HQ, their modification with Au−In core−shellnanoparticles induces a pronounced shift of the oxidation peakto lower potentials, i.e., facilitated oxidation. The response ofthe different electrodes was correlated with the initial composition of the bimetallic nanoparticle cores, which in turn determinedthe amount of Au and In stabilized on the surface of the amorphous Au−In oxide shells available for the electrochemical reaction.While adding core−shell nanostructures with different compositions of the alloy core facilitates the electrocatalytic (reduction-)oxidation of HQ, the activity is highest for particles with AuIn cores (i.e., a Au:In ratio of 1). This optimal system is found tofollow a single pathway, the two-electron oxidation of the quinone−hydroquinone couple, which gives rise to high oxidationpeaks and is most effective in facilitating the electrode-to-analyte charge transfer and thus detection. The limits of detection(LOD) decreased when increasing the amount of Au exposed on the surface of the amorphous Au−In oxide shells. The LODswere in the range of 10−5−10−6 M and were lower than those obtained using bulk Au.
PB American Chemical Society
SN 1932-7447
YR 2015
FD 2015
LK http://uvadoc.uva.es/handle/10324/20891
UL http://uvadoc.uva.es/handle/10324/20891
LA eng
NO J. Phys. Chem. C 2015, 119, 25100−25107
NO Producción Científica
DS UVaDOC
RD 22-feb-2020