High-Performance Ti₃C₂T_x-MXene/Mycelium Hybrid Membrane for Efficient Lead Remediation: Design and Mechanistic Insights

This study presents a hybrid microfiltration technology designed for high-performance lead (Pb(II)) remediation, especially from aqueous solutions with high Pb(II) concentrations, by utilizing two-dimensional (2D) Ti₃C₂T_x-MXene layers deposited on dry mycelium membranes. The hybrid Ti₃C₂T_x-MXene/mycelium (MyMX) membranes were fabricated via a single-step electrochemical deposition (ECD) technique, which enabled a uniform coating of 2D Ti₃C₂T_x-MXene onto individual hyphal fibers of a prefabricated mycelium membrane. Optimized ECD parameters for high Pb(II) uptake were identified using scanning electron microscopy and energy-dispersive X-ray spectroscopy. In immersion-based (no-flow) Pb(II) remediation experiments, MyMX membranes demonstrated significantly high Pb(II) removal efficiency (>87-99%) and rapid sorption kinetics across an initial Pb(II) concentration range of 60-1500 ppm in both single-ion and co-ion solutions. The enhanced Pb(II) sorption was attributed to electrostatic interactions and surface complexation assisted by hyphal surface proteins and Ti₃C₂T_x-MXene functional groups, as confirmed by infrared and X-ray photoelectron spectroscopies. In cross-flow studies, the MyMX membranes achieved a Pb(II) sorption capacity of ∼1347 mg/g while maintaining a high permeation rate of 51,800 L m^-2 bar^-1 h^-1 at 1500 ppm Pb(II), surpassing the performance of various polymer-based and MXene-based microporous membranes for heavy metal remediation. The biomaterial-based hybrid MyMX membrane represents a significant advancement in water treatment technology, providing a cost-effective, sustainable solution for Pb(II) remediation in contaminated water sources.