Abstract:
This research work aimed to develop the cost effective, sensitive, precise and adequate
techniques equipped with glassy carbon electrode modified with nanocomposite(NCs) for
the electrochemical detection of Pb2+ and Cu2+ions. Cadmium oxide based NCs were
prepared by a sol-gel method using metal precursor cadmium acetate dihydrateas
stabilizing agent.The NCs was kept in desiccators at room temperature for further surface
characterization and EC tests.The Ag-CdO/PANI NCs were prepared by in situ chemical
oxidative polymerisation of aniline with Ag doped CdO nanoparticles in an aqueous
solution of ammonium per sulfate (APS).The synthesized NCs were subjected for
spectroscopic and structural characterization using FTIR, SEM and XRD respectively. From
the FT-IR spectrum, it is strongly confirmed that the nanoparticles are well incorporated
into the PANI molecular chain and in-situ polymerization was successful during surface
modification of Ag-doped CdO nanoparticles with PANI. The maximum diffraction peak
for PANI was observed around 2θ = 25.1° which can be ascribed to periodically parallel
and perpendicular polymer chains. The XRD pattern of nanocomposite was observed at
2θ = 25.0°, 27.0°, 28.0°, 35.1° and 37.5° describe that, the pattern represent the cubic
structure of CdO NPs, Ag-CdO and PANI That the sizes NPs of CdO were about (17.44nm)
using from the most intense XRD peak. Nanocomposites show high electrical conductivity
compared to pure PANI. The conductivity of nanocomposites increases with increasing of
CdO content because of the new conductivity passageways formed by embedded
nanoparticles of CdO.
Electrochemical characterization was carried out by cyclic voltammetry in potassium
chloride solutions. The nanocomposite modified GCE in particular Ag-CdO/PANI was
successfully applied for electrochemical detection of Cu2+ and Pb2+ using cyclic
voltammetry method. Among the GCE surface modified with nanocomposites, Ag CdO/P/G/Pb2+exhibited the largest anodic and cathodic currents among the surface
modified GCE for electrochemical detection of copper and lead heavy metals (Ipc,-0.046
mA and Ipa, 0.039 mA).
