Facile and Efficient Self-template Synthesis of Core-coronal-shell ZnO@ZIF-8 Nanohybrid Using Ascorbic Acid and its Application for Arsenic Removal

Abstract

In the present contribution, a facile and efficient protocol for synthesis a nanohybrid structure of core-coronal-shell ZnO@ZIF-8 using ascorbic acid (ZnO@AA/ZIF-8) as a new adsorbent for arsenic removal from water has been represented. For this purpose, the ZnO nanospheres were synthesized by a green and simple method followed by coating with ascorbic acid (AA) to modify their surface to achieve better growth of ZIF-8 on the surface of ZnO. After that, the core-coronal-shell ZnO@ZIF-8 nanohybrid obtained via in situ ZIF-8 formation using the dispersion of ZnO (as a core) in an ethanol solution only including 2-methylimidazole under moderate conditions. Here, ZnO is utilized as a template (core) as well as the metal node for ZIF-8 synthesis. The as-synthesized ZnO and ZnO@AA/ZIF-8 structures were characterized by different techniques such as XRD, FT-IR, TGA, and, SEM-EDS. The analyses data confirmed the benefit of the method for the preparation of this new nanohybrid. The nanostructured ZnO@AA/ZIF-8 exhibited high efficiency in the removal of arsenic from water. The obtained results confirmed that core-coronal-shell metal oxide@MOF nanohybrid could be introduced as efficient candidates for heavy metals removal for practical applications.