Zeolitic imidazolate framework@hydrogen titanate nanotubes for efficient adsorption and catalytic oxidation of organic dyes and microplastics

Abstract

Metal-organic frameworks (MOFs) have significant promise as materials for many environmental applications, namely in the realm of water treatment. In this study, we produced a nanocomposite material by combining zeolitic imidazolate frameworks (ZIF-67) with hydrogen titanate nanotubes (HTNT) at ambient temperature. The materials, namely HTNT, ZIF-67, and HTNT@ZIF-67, were analyzed and employed for the adsorption and catalytic oxidation of water pollutants such as organic dyes (fluorescein acid (FL), Rhodamine B (RhB), direct blue I (DB), and basic fuchsin (BF)) and microplastics extracted from personal care and cosmetics products. The HTNT@ZIF-67 nanocomposite exhibited dye removal efficiencies of 99% and 97% for adsorption and catalytic oxidation by hydrogen peroxide (H2O2), respectively. ZIF-67 exhibits the most rapid disintegration rate among the tested substances, with rates of 517, 439, 1764, 1764, and 1621 mL/min·g for H2O2 and H2O2 in the presence of FL, RhB, DB, and BF, respectively. The catalytic degradation process may be used for up to six cycles, while maintaining an efficiency of 78%. Catalysts based on ZIF-67, such as HTNT@ZIF-67, show great potential for removal targeting organic contaminants such dyes and microplastics.