Nanoarchitectonics of molybdenum rich crown shaped polyoxometalates based ionic liquids reinforced on magnetic nanoparticles for the removal of microplastics and heavy metals from water

The removal of heavy metal ions and microplastics from water remains a significant challenge. This study addresses this issue by introducing mesoporous composites consisting of polyoxometalate-based ionic liquids reinforced on magnetic silica-coated nanoparticles. The composites, Q 8 [Mo 54 ] @ SiO 2 @ Fe 3 O 4 , Q 10 [Mo 54 ] @ SiO 2 @ Fe 3 O 4 , Q 8 [Mo 46 ] @ SiO 2 @ Fe 3 O 4 , and Q 10 [Mo 46 ] @ SiO 2 @ Fe 3 O 4 , are derived from the combination of molybdenum clusters ([Mo 46 ] 21- and [Mo 54 ] 26- ) with tetraoctylammonium and tetradecylammonium counter cations, resulting in ionic liquids Q 8 [Mo 54 ], Q 10 [Mo 54 ], Q 8 [Mo 46 ], and Q 10 [Mo 46 ], that are subsequently coated onto SiO 2 @ Fe 3 O 4 . A comprehensive set of characterization techniques was employed to evaluate the properties of these materials. Fourier transform infrared spectroscopy, UV–vis spectroscopy, thermogravimetric analysis, differential scanning calorimetry, cyclic voltammetry, rheology, elemental analysis, inductively coupled plasma atomic emission spectroscopy, powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, dynamic light scattering, high resolution transmission electron microscopy, and N 2 adsorption-desorption isotherms and gas chromatography-mass spectrometry were utilized. These analyses confirm the composites amorphous surface morphology and large specific surface areas and efficient adsorption properties. Inductively coupled plasma atomic emission spectroscopy results demonstrated remarkable heavy metal ions removal efficiencies, ranging from 79.5 % to 99.3 % in laboratory water and from 92 % to 99 % in industrial wastewater. Additionally, dynamic light scattering analysis showed a 100 % removal efficiency for polyvinyl chloride beads in laboratory water and 95–98 % in industrial wastewater. All composites displays excellent reusability and stability over five cycles. • Hydrophobic polyoxometalate-based ionic liquids reinforce on magnetic nanoparticles, utilized for the removal of the microplastics from water. • Four different polyoxometalate-ionic liquid-based composites, demonstrated high efficiency in removing heavy metal ions. • Long-chain quaternary ammonium cations enhanced the hydrophobicity of the composites, resulting in better adsorption. • Achieved exceptional removal efficiency and reusability with good stability, highlighting the potential of composites for practical environmental remediation.