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Selective growth of Ti³⁺/TiO₂/CNT and Ti³⁺/TiO₂/C nanocomposite for enhanced visible-light utilization to degrade organic pollutants by lowering TiO₂-bandgap.

ABSTRACT: A convenient route was developed for the selective preparation of two stable nanocomposites, Ti³⁺/TiO₂/CNT (labeled as TTOC-1 and TTOC-3) and Ti³⁺/TiO₂/carbon layer (labeled as TTOC-2), from the same precursor by varying the amount of single-walled carbon nanotubes used in the synthesis. TiO₂ is an effective photocatalyst; however, its wide bandgap limits its usefulness to the UV region. As a solution to this problem, our prepared nanocomposites exhibit a small bandgap and wide visible-light (VL) absorption because of the introduction of carbonaceous species and Ti³⁺ vacancies. The photocatalytic efficiency of the nanocomposites was examined via the degradation of methylene blue dye under VL. Excellent photocatalytic activity of 83%, 98%, and 93% was observed for TTOC-1, TTOC-2, and TTOC-3 nanocomposites within 25 min. In addition, the photocatalytic degradation efficiency of TTOC-2 toward methyl orange, phenol, rhodamine B, and congo red was 28%, 69%, 71%, and 91%, respectively, under similar experimental conditions after 25 min. Higher reusability and structural integrity of the as-synthesized photocatalyst were confirmed within five consecutive runs by photocatalytic test and X-ray diffraction analysis, respectively. The resulting nanocomposites provide new insights into the development of VL-active and stable photocatalysts with high efficiencies.

SUBMITTER: Akter J

PROVIDER: S-EPMC8096813 | biostudies-literature |

REPOSITORIES: biostudies-literature

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