Investigation of morphologies and characterization of rare earth metal samarium hexacyanoferrate and its composite with surfactant intercalated graphene oxide for sensor applications

Abstract

Herein, we report a facile electrochemical approach for the hierarchical growth of samarium hexacyanoferrate (SmHCF) on surfactant intercalated reduced graphene oxide (SRGO). The fabricated SRGO/SmHCF modified glassy carbon electrode (GCE) has excellent electrocatalytic activity towards catechol (CC) sensor applications. The sunflower-like SmHCF microparticles were achieved by controlling the number of cycles during the electrodeposition process. In addition, the electrolyte plays a key role in the morphology of SmHCF and was investigated using different electrochemical techniques. The as-prepared SmHCF microparticles were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and Fourier transform infrared (FT-IR) spectroscopy. In addition, electrochemical impedance spectroscopy (EIS) was carried out to understand the mechanism of interfacial electrochemical reactions on the proposed SmHCF modified glassy carbon electrode (GCE). The obtained EIS data confirmed that the electron transfer rate at SmHCF/GCE was faster than bare GCE. The electrochemical detection of CC using the SRGO/SmHCF modified GCE was performed by cyclic voltammetry and difference pulse voltammetry. The fabricated modified GCE exhibits a good linear range from 50 μM to 250 μM, with a limit of detection (LOD) of 0.38 μM and a sensitivity of 0.430 μA μM⁻¹ cm² for the CC electrochemical sensor.