Dielectric and Photocatalytic Performance of Heterostructured Nanocomposites of Cobalt and Nickel Oxides Embedded in Zeolite 4A Matrix.

Abstract Organic pollutants like malachite green pose severe environmental risks due to their toxicity and persistence in water bodies. This study explores an eco‐friendly solution for their removal via photocatalytic degradation using cobalt and nickel oxide‐doped zeolite nanocomposites (CoZ NC & NiZ NC), synthesized through a co‐precipitation method. X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy‐dispersive X‐ray (EDX) analyses confirm the formation of FCC‐structured nanometal oxides on the zeolite matrix. Optical spectral analysis reveals low bandgap energies (2.84 eV for CoZ NC and 2.81 eV for NiZ NC), enabling efficient photocatalysis under visible light. These nanocomposites demonstrated effective photodegradation of malachite green, showcasing their environmental remediation potential. Dielectric studies indicate significantly higher dielectric permittivity in CoZ NC and NiZ NC compared to pristine zeolite. This enhancement is attributed to internal barrier layer capacitance arising from variable oxidation states of metal oxide nanoparticles and interfacial space charge polarization between the zeolite matrix and metal dopants. Uniformly distributed cobalt oxide nanoparticles provide superior permittivity in CoZ NC compared to the unevenly arranged nickel oxide in NiZ NC. Additionally, lower dissipation factors in CoZ NC and NiZ NC highlight their suitability as promising k‐dielectric materials for energy storage applications.