In situ turning defects of exfoliated Ti3C2 MXene into Fenton-like catalytic active sites

Proc Natl Acad Sci U S A. 2023 Jan 3;120(1):e2210211120. doi: 10.1073/pnas.2210211120. Epub 2022 Dec 27.

Abstract

Controllable in situ formation of nanoclusters with discrete active sites is highly desirable in heterogeneous catalysis. Herein, a titanium oxide-based Fenton-like catalyst is constructed using exfoliated Ti3C2 MXene as a template. Theoretical calculations reveal that a redox reaction between the surface Ti-deficit vacancies of the exfoliated Ti3C2 MXene and H2O2 molecules facilitates the in situ conversion of surface defects into titanium oxide nanoclusters anchoring on amorphous carbon (TiOx@C). The presence of mixed-valence Tiδ+ (δ = 0, 2, 3, and 4) within TiOx@C is confirmed by X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) characterizations. The abundant surface defects within TiOx@C effectively promote the generation of reactive oxygen species (ROS) leading to superior and stable Fenton-like catalytic degradation of atrazine, a typical agricultural herbicide. Such an in situ construction of Fenton-like catalysts through defect engineering also applies to other MXene family materials, such as V2C and Nb2C.

Keywords: MXene; heterogeneous catalysis; in situ; multivalence; template synthesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Catalytic Domain
  • Hydrogen Peroxide* / chemistry
  • Titanium* / chemistry

Substances

  • Hydrogen Peroxide
  • titanium dioxide
  • Titanium
  • MXene