Synergistic in situ growth of a MOF on the surface of Ti3C2Tx MXene nanosheets with different tannic acid (TA) ratios for the photocatalytic degradation of pollutants†

The integration of a two-dimensional (2D) transition metal carbide (MXene) with metal–organic frameworks (MOFs) presents a promising avenue for addressing the limitations of MXene materials in various applications. In this study, we report the fabrication of a novel photocatalyst by in situ-growth self-assembly, where Ti₃C₂T_x MXene serves as a substrate for immobilizing ZIF-8 MOFs. This composite, Ti₃C₂T_x@ZIF-8, is further modified with tannic acid (TA) and polyphenol compounds to create a cross-linked network, enhancing the heterogeneous interfaces crucial for efficient photocatalysis. Varying concentrations of tannic acid (10, 20, and 30 mg) were explored to optimize photocatalyst performance. Structural characterization confirms the successful synthesis of Ti₃C₂T_x@ZIF-8@TA composites, revealing their unique network topology. The prepared ZIF-8, Ti₃C₂T_x@TA, Ti₃C₂T_x/ZIF-8@TA10, Ti₃C₂T_x/ZIF-8@TA20 and Ti₃C₂T_x/ZIF-8@TA30 photocatalysts were characterized by various techniques (SEM, EDX, FTIR, XRD, TGA, DRS, and BET surface area measurements). Under visible light irradiation, the photocatalyst demonstrates remarkable degradation efficiencies, with RhB, Congo red and methyl orange dyes achieving approximate degradation rates of 87%, 85%, and 79%, respectively, within 60 minutes. Notably, the photocatalyst exhibits low energy consumption, affordability, non-toxicity, and environmental compatibility, underscoring its practical potential for wastewater treatment applications. This work highlights the advancement in MXene-based photocatalysts and their significant impact on pollutant removal from wastewater.