Abstract:
In this era of science and technology, factories setup and industrial advancement has
expanded by leaps and bounds. The advancement though being in human favor has also
caused devastating effects not only on human but also on his environment in the form of
industrial pollution. In this regard leather, tanning, pharmaceuticals, food industries have
garnered the limelight of being responsible for disposal of life threatening and highly toxic
chemicals into the environment. One of them being dihydroxybenzenes, the detection of
which has faced tremendous issues owing to the isomeric interference by them. This field of
research focuses on the development of electrochemical sensors that could not only
efficiently detect catechol (one of the isomer of dihydroxybenzene) but may also lead to its
sensitive and selective detection without any kind of interference from other isomers of
dihydroxybenzene.
During the course of this research graphene oxide (GO) have been synthesized by modified
Hummers and reduced graphene oxide (rGO) by chemical reduction method.
Tetraphenylporphyrin (TPP) by Adler Longo method and zinc tetraphenylporphyrin (ZnTPP)
by modified Adler Longo method. The composites of rGO-TPP and rGO-ZnTPP with 3
different ratios were employed for catechol detection. The composite formation was
confirmed by FT-IR, UV-vis spectroscopy, SEM and EDS analysis. Among different
composites rGO-ZnTPP (1:2) exhibited highest sensitivity towards catechol detection with a
peak current of 126 μA. When subjected to a mixture of catechol and its competitive isomer
hydroquinone the fabricated sensor rGO-ZnTPP (1:2)/GCE showed exceptional selectivity
with two distinct peaks at varying potentials depicting the presence of two different species in
the mixture. The peak to peak separation between hydroquinone and catechol came out to be
116 mV. The fabricated sensor rGO-ZnTPP/GCE also exhibited excellent limit of detection
of 67 μM and exceptional sensitivity of 937.29 μAmM-1 cm-2
