Photocatalytic Activity of the Oxidation Stabilized Ti₃C₂T_x MXene in Decomposing Methylene Blue, Bromocresol Green and Commercial Textile Dye

Abstract

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.

Ambient Processed rGO/Ti3CNTx MXene Thin Film with High Oxidation Stability, Photosensitivity, and Self-Cleaning Potential

“…Therefore, we tested the self-cleaning ability of the films under UV or white light irradiation using discoloration of a model cationic dye, rhodamine B (RhB). The negative zeta potential of the flakes with functional groups (−F and −O terminations) on the surface helps MXene effectively adsorb cationic dyes, such as RhB. , Additionally, we also tested the RhB adsorption on the bare rGO thin-film surface. In contrast to the MXene-based thin film, we found that bare rGO showed a poor interaction with RhB (Figure S21).…”

Separation and Photodegradation of Dye-Containing Oil/Water Mixtures with a Photothermally Responsive PNIPAm-MXene/PAN-PNIPAm Nanofibrous Hydrogel Membrane

“…MXene has a high electron migration rate due to the presence of titanium atoms in its structure, which can serve as an electron acceptor to facilitate the transport of photogenerated carriers and prohibit their complexation. 36 In addition, the switchable wettability of the PMPP membranes shows significant potential for continuous separation and in situ photodegradation of heavy oil/water/ light oil ternary mixtures. The well-controlled separation process is shown in Figure 5a and Video S2.…”

“…It is also easy to integrate photothermal materials with the PNIPAm hydrogel to create photothermally stimulated responsive composite hydrogels . As an emerging two-dimensional material with a significant variety of end groups (such as −O, −OH, and −F), MXene has attracted much interest in the fields of oil/water separation and photodegradation due to its excellent light absorption characteristics and exceptional charge separation efficiency for photodegradation . By mixing MXene with PNIPAm, PNIPAm can achieve photothermally responsive behavior by utilizing the outstanding photothermal properties of MXene.…”

Wet‐Chemical Etching and Delamination of MoAlB into MBene and Its Outstanding Photocatalytic Performance

“…[ 9–12 ] These fascinating materials can boost the generation and utilization of charge carriers, the most active in pollutant decomposition. [ 13–15 ] Their activity is confined to their ultrathin nature, which concentrates quantum effects in the planar dimension. [ 16,17 ]…”

“…[9][10][11][12] These fascinating materials can boost the generation and utilization of charge carriers, the most active in pollutant decomposition. [13][14][15] Their activity is confined to their ultrathin nature, which concentrates quantum effects in the planar dimension. [16,17] An excellent example of such 2D materials is the MXene family, named early transition metal carbides and nitrides.…”