Photocatalytic oxidation of formaldehyde under visible light using BiVO4-TiO2 synthesized via ultrasonic blending

Environ Sci Pollut Res Int. 2024 Apr;31(20):30085-30098. doi: 10.1007/s11356-024-33192-2. Epub 2024 Apr 10.

Abstract

Formaldehyde (HCHO) is one of the primary indoor air pollutants, and efficiently eliminating it, especially at low concentrations, remains challenging. In this study, BiVO4-TiO2 catalyst was developed using ultrasonic blending technology for the photocatalytic oxidation of low-level indoor HCHO. The crystal structure, surface morphology, element distribution, and active oxidation species of the catalyst were examined using XRD, SEM, TEM, UV-Vis, EDS, and ESR techniques. Our results demonstrated that the BiVO4-TiO2 catalyst, prepared by ultrasonic blending, exhibited good oxidation performance and stability. The HCHO concentration reduced from 1.050 to 0.030 mg/m3 within 48 h, achieving a removal rate of 97.1%. The synergy between BiVO4 and TiO2 enhanced the efficiency of separating photogenerated carriers and minimized the likelihood of recombination between photogenerated electrons and holes. Additionally, this synergy significantly enhanced the presence of hydroxyl radicals (·OH) on the catalyst, resulting in an oxidation performance superior to that of either BiVO4 or TiO2. Our research offers valuable insights for the development of new photocatalysts to address HCHO pollution.

Keywords: Bismuth vanadate; Formaldehyde; Heterojunction; Photocatalytic oxidation; Titanium dioxide.

MeSH terms

  • Bismuth* / chemistry
  • Catalysis
  • Formaldehyde* / chemistry
  • Light
  • Oxidation-Reduction*
  • Titanium* / chemistry
  • Ultrasonics
  • Vanadates* / chemistry

Substances

  • Formaldehyde
  • Titanium
  • titanium dioxide
  • Vanadates
  • bismuth vanadium tetraoxide
  • Bismuth