Simple Preparation and Characterization of Hierarchical Flower-like NiCo 2 O 4 Nanoplates: Applications for Sunset Yellow Electrochemical Analysis.

The current work was performed to construct a novel electrochemical sensing system for determination of sunset yellow via the modification of screen-printed graphite electrode modified with hierarchical flower-like NiCo 2 O 4 nanoplates (NiCo 2 O 4 /SPGE). The prepared material (hierarchical flower-like NiCo 2 O 4 nanoplates) was analyzed by diverse microscopic and spectroscopic approaches for the crystallinity, composition, and morphology. Chronoamperometry, differential pulse voltammetry, linear sweep voltammetry, and cyclic voltammetry were used for determination of the electrochemical behavior of sunset yellow. The as-fabricated sensor had appreciable electro-catalytic performance and current sensitivity in detecting the sunset yellow. There were some advantages for NiCo 2 O 4 /SPGE under the optimized circumstances of sunset yellow determination, including a broad dynamic linear between 0.02 and 145.0 µM, high sensitivity of 0.67 μA/(μM.cm 2 ), and a narrow limit of detection of 0.008 μM. The practical applicability of the proposed sensor was verified by determining the sunset yellow in real matrices, with satisfactory recoveries.