Synthesis, Characterization, and Multifunctional Evaluation of CdO–Fe₂O₃ Nanocomposite for Electrochemical Sensing and Antifungal Applications

Abstract

This study reports the synthesis, characterization, and functional evaluation of CdO–Fe₂O₃ nanocomposite for electrochemical sensing and antifungal applications. The binary nanocomposite was successfully synthesized via a controlled co-precipitation method using cadmium nitrate tetrahydrate and iron(III) nitrate nonahydrate as precursors, with sodium hydroxide as the precipitating agent. Fourier transform infrared spectroscopy confirmed the formation of the mixed metal oxide lattice, with characteristic Cd–O and Fe–O vibrational bands observed at 915 cm⁻¹ and 543 cm⁻¹, respectively. The fabricated nanocomposite-modified glassy carbon electrode (NC-B/GCE) demonstrated excellent electrochemical performance for urea detection, exhibiting a linear response across a concentration range of 5 to 50 ppb with a clean blank reading of 0.00 µA. The sensor showed high sensitivity and reproducibility, with peak currents increasing proportionally from 1.85 µA at 5 ppb to 5.18 µA at 50 ppb. Antifungal evaluation against mushroom fungi revealed no inhibition at the tested concentrations (100 and 50 mm), though the positive control confirmed the validity of the assay. The findings suggest that CdO–Fe₂O₃ nanocomposite holds promise as a sensitive electrochemical sensing platform, while its antifungal efficacy against mushroom fungi requires further optimization. This work contributes to the development of multifunctional nanomaterials for environmental monitoring and agricultural applications.