TiVCTX MXene/Graphene Nanosheet-Based Aerogels for Removal of Organic Contaminants from Wastewater

Efficient removal of broad-spectrum organic pollutants is crucial in wastewater treatment. This research focuses on the synthesis of three-dimensional TiVCTX MXene/graphene nanosheet-based aerogels, known as TiVCTX/GAs, using a straightforward hydrothermal self-assembly method, followed by freeze-drying. The integration of bimetallic MXene and graphene aerogel in TiVCTX/GAs results in an impressive broad-spectrum removal capability for multiple organic contaminants from wastewater. TiVCTX/GAs exhibit effective adsorption of various dyes and drugs, with adsorption capacities reaching 319.67, 303.45, 229.97, 217.87, and 283.38 mg·g–1 for methylene blue, rhodamine B, Congo red, methyl orange, and tetracycline hydrochloride, respectively. To fully comprehend the adsorption mechanism of TiVCTX/GAs, various models for the adsorption process were examined including kinetic, isothermal, and thermodynamic models. The adsorption process aligns with the Langmuir model and the pseudo-second-order kinetic model. The intraparticle diffusion model suggests that intraparticle diffusion is not the only rate-controlling step. Moreover, thermodynamic analysis indicates that the adsorption process by TiVCTX/GAs is spontaneous. These aerogels also effectively remove common oils and organic solvents from wastewater through absorption treatment with a substantial absorption capacity ranging from 40 to 90 g·g–1. Particularly, for high-viscosity oils that are challenging to absorb, TiVCTX/GAs demonstrate remarkable absorption ability by reducing their viscosity through photothermal heating. Overall, TiVCTX/GAs show great promise as versatile adsorbents and absorbers for efficiently and comprehensively removing various organic contaminants from wastewater.