Polypropylene (PP) is a thermoplastic polymer widely used as a medical textile in healthcare applications due to its low cost and superior performance. However, it does not show antibacterial properties leading to the possibility of pathogen transmission. Herein, we have developed an antibacterial medical fabric by facile self-assembly of delaminated two-dimensional (2D) Ti 3 C 2 T x MXene flakes bristling on the surface of PP fibers. The increasing amount of MXene in the coating solution from 1 up to 32 mg/mL allowed for edge-on assembly of MXene flakes on the PP surface and tracking the evolution of the band gap for a restacked structure. Characterization of the PP/Ti 3 C 2 T x nanocomposite has proven that it exhibited highly effective antibacterial, robust coating, and chemically/thermally stable properties. The in vitro microbiological studies against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus have shown that PP/Ti 3 C 2 T x reduced the bacterial viability up to 100%, as driven by synergistic membrane stress mediated by physical contact and light-induced reactive oxygen species (ROS) generation. Moreover, the use of L-ascorbic acid for MXene stabilization allowed for achieving excellent thermal stability of the PP/Ti 3 C 2 T x nanocomposite upon accelerated thermal aging. Collectively, this work provides a facile surface engineering strategy for designing medical fabrics with outstanding functional performances. By demonstrating the exceptional performance of the stabilized MXene in a self-assembly nanocomposite structure, we are opening the door for MXenes to be applied in other biomedical fields.

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Two‐dimensional MXenes are excellent photocatalysts. However, their low oxidation stability makes controlling photocatalytic processes challenging. For the first time, this work elucidates the influence of the oxidation stabilization of model 2D Ti3C2Tx MXene on its optical and photocatalytic properties. The delaminated MXene is synthesized via two well‐established approaches: hydrofluoric acid/tetramethylammonium hydroxide (TMAOH‐MXene) and minimum intensive layer delamination with hydrochloric acid/lithium fluoride (MILD‐MXene) and then stabilized by L‐ascorbic acid. Both MXenes at a minimal concentration of 32 mg L−1 show almost 100% effectiveness in the 180‐min photocatalytic decomposition of 25 mg L−1 model methylene blue and bromocresol green dyes. Industrial viability is achieved by decomposing a commercial textile dye having 100 times higher concentration than that of model dyes. In such conditions, MILD‐MXene is the most efficient due to less wide optical band gap than TMAOH‐MXene. The MILD‐MXene required only few seconds of UV light, simulated white light, or 500 nm (cyan) light irradiation to fully decompose the dye. The photocatalytic mechanism of action is associated with the interplay between surface dye adsorption and the reactive oxygen species generated by MXene under light irradiation. Importantly, both MXenes are successfully reused and retained approximately 70% of their activity.

Rapidly developing nanotechnologies and their integration in daily applications may threaten the natural environment. While green methods of decomposing organic pollutants have reached maturity, remediation of inorganic crystalline contaminants is major problem due to their low biotransformation susceptibility and the lack of understanding of material surface-organism interactions. Herein, we have used model inorganic 2D Nb-based MXenes coupled with a facile shape parameters analysis approach to track the mechanism of bioremediating 2D ceramic nanomaterials with green microalgae Raphidocelis subcapitata. We have found that microalgae decomposed the Nb-based MXenes due to surface-related physicochemical interactions. Initially, single and few-layered MXene nanoflakes attached to microalgae surfaces, which slightly reduced algal growth. But with prolonged surface interaction, the microalgae oxidized MXene nanoflakes and further decomposed them into NbO and Nb2O5. Since these oxides were nontoxic to microalgal cells, they consumed Nb-oxide nanoparticles by an uptake mechanism thus enabling further microalgae recovery after 72 h of water treatment. The uptake-associated nutritional effects were also reflected by cells’ increased size, smoothed shape and changed growth rates. Based on these findings, we conclude that short- and long-term presence of Nb-based MXenes in freshwater ecosystems might cause only negligible environmental effects. Notably, by using 2D nanomaterials as a model system, we show evidence of the possibility of tracking even fine material shape transformations. In general, this study answers an important fundamental question about the surface interaction-associated processes that drive the mechanism of 2D nanomaterials’ bioremediation as well as provides the fundamental basis for further short- and long-term investigations on the environmental effects of inorganic crystalline nanomaterials.