Novel and green synthesis of BiVO4 and GO/BiVO4 photocatalysts for efficient dyes degradation under blue LED illumination

• Published in: Ceramics international 2022-01, Vol.48 (1), p.1264-1276
• Main Authors: Moral-Rodríguez, A.I., Quintana, M., Leyva-Ramos, R., Ojeda-Galván, H.J., Oros-Ruiz, S., Peralta-Rodríguez, R.D., Mendoza-Mendoza, E.
• Format: Article
• Language: English
• Subjects: Bismuth vanadate; Graphene oxide; Green synthesis; LEDs; Photodegradation
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2021.09.211

A straightforward, high-yield route was followed to produce visible light active BiVO4 (BV)-based catalysts through the novel, green approaches: metathesis and metathesis-assisted molten salts. The catalysts prepared at room temperature (BV-RT) and 350 °C for 12 h (BV350/12) exhibited spherical-like and highly crystalline plate-like particles, respectively. A novel BV catalyst was prepared by adding graphite oxide, GO/BV. The synthesis conditions affected crystallite size, crystallinity, optical edge, energy gap, specific area characteristics, and photocatalytic activity. GO/BV achieved 100% rhodamine B (RhB) degradation irradiated (300 min) with low-power blue LEDs. The initial reaction rate (-r0) of RhB using the GO/BV was 4.57, 3.42 and 1.31-fold faster than BV-RT, BV350/12, and BV350/2. Catalyst dosage and RhB initial concentration on the photoactivity of GO/BV were analyzed. Trapping experiments established that holes and hydroxyl radicals are the main oxidative species causing RhB degradation, and the mechanism was postulated based on GO/BV. Reusability tests confirmed GO/BV chemical stability. GO/BV reached 74% photodegradation of methylene blue (MB). The photodegradation of the RhB + MB mixture using GO/BV showed that the coexistence of MB diminished the RhB degradation to 86%. •A novel, green route was applied to prepare nanostructured BiVO4 photocatalysts.•Low power blue LEDs were used as effective irradiation source.•BV350/2 h and GO/BV achieved RhB photodegradation of 96 and 100% within 300 min.•GO/BV photocatalytic performance showed 74% MB degradation.•RhB + MB photodegradation over GO/BV showed higher activity towards MB than RhB.