Zeolitic imidazolate framework-67 functionalized cellulose hybrid aerogel: an environmentally friendly candidate for dye removal

Abstract

An eco-friendly, low-cost, and highly efficient adsorbent based on biomass material, cellulose matrix-supported metal-organic-framework (MOF) hybrid aerogel (ZIF-67@CA), was designed and prepared by in situ growth of ZIF-67 nanoparticles on pre-synthesized chemically crosslinked cellulose aerogel. The chemical structure and surface morphology of as-prepared ZIF-67@CA were characterized by various methods. Analysis results confirmed the successful formation of a densely coated layer of ZIF-67 on the surface of the cellulosic aerogel. Owing to its large specific surface area and electrostatic attraction of ZIF-67 with methyl orange (MO), ZIF-67@CA exhibited high adsorption capacity of up to 617 mg g⁻¹ for MO, which was more than four times higher than that of the pristine cellulose aerogel. Additionally, ZIF-67@CA could selectively separate anionic dye from the dye mixture and maintain 90% adsorptivity even after five cycles of repeated usage. Hence, this work provided a feasible solution and scalable platform for the functional design and rational manufacture of MOF-based cellulose aerogel. Moreover, the versatility of its structural design makes it a promising adsorbent material for wide application range of wastewater treatment.