Microwave-assisted synthesis of α-Fe2O3/ZnFe2O4/ZnO ternary hybrid nanostructures for photocatalytic applications

Solar-driven highly efficient photocatalytic decomposition of toxic organic contaminants using magnetically separable alpha-Fe2O3/ZnFe2O4/ZnO ternary hybrid nanodiscs is reported. alpha-Fe2O3/ZnFe2O4/ZnO ternary hybrid nanostructures were synthesized by microwave-assisted co-precipitation and simple co-precipitation methods and well characterized by XRD, micro-Raman, FESEM and UV-vis spectroscopy. FESEM micrographs revealed nanodiscs in case of microwave-assisted co-precipitation whereas nanoparticles and their aggregates were formed under co-precipitation combined with calcination. XRD and Raman studies confirmed the hybrid nature of prepared alpha-Fe2O3/ZnFe2O4/ZnO nanostructures. Photocatalytic performance of alpha-Fe2O3/ZnFe2O4/ZnO hybrid nanostructures was investigated by carrying out the photodegradation of organic dyes MB and MG under solar light illumination. The prepared alpha-Fe2O3/ZnFe2O4/ZnO ternary hybrid magnetic nanodiscs decomposed MB and MG dyes in only 32 and 24 min, respectively. alpha-Fe2O3/ZnFe2O4/ZnO hybrid nanodiscs showed excellent photocatalytic performance together with reusability and easy magnetic separation demonstrating its suitability for solar-driven photocatalytic water purification applications. In-situ scavenger studies showed center dot OH radicals are the main active radicals in solar-driven photocatalysis by alpha-Fe2O3/ZnFe2O4/ZnO nanodiscs. The tentative mechanism of growth of alpha-Fe2O3/ZnFe2O4/ZnO ternary hybrid nanodiscs and the photocatalytic mechanism are discussed.

Automated summary

This study reports the use of magnetically separable alpha-Fe2O3/ZnFe2O4/ZnO ternary hybrid nanodiscs for solar-driven highly efficient photocatalytic decomposition of toxic organic contaminants. The hybrid nanostructures showed excellent photocatalytic performance under solar light illumination, efficiently decomposing organic dyes and demonstrating reusability and easy magnetic separation. In-situ scavenger studies identified center dot OH radicals as the main active radicals in the photocatalysis process.