TiO2@hollow carbon spheres: A photocatalyst for hydrogen generation under visible irradiation

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2021-08, Vol.417, p.113355, Article 113355
• Main Authors: Boudjemaa, A., Nongwe, I., Mutuma, B.K., Matsoso, B.J., Bachari, K., Coville, N.J.
• Format: Article
• Language: English
• Subjects: Core-shell; Hollow carbon spheres; Hydrogen; LED irradiation; Photocatalysis; TiO2
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2021.113355

[Display omitted] •TiO2@HCS photocatalyst with different amount of TiO2 was successful prepared.•The photocatalysts exhibited excellent photocatalytic activity for hydrogen evolution under visible light irradiation.•Carbon covering of the surface of TiO2 improved the photo-reactivity. Hydrogen photoproduction using both hollow carbon spheres (HCSs) and titania modified hollow carbon spheres (TiO2@HCSs) has been performed under visible-light-emitting diode (LED) irradiation. The TiO2@HCSs had diameters of ca. 140−150 nm with Shell width of 20−35 nm, depending on the TiO2 loading. Raman, FTIR and XPS results indicated the formation of core-shell TiO2 modified HCSs nanostructures. Upon visible-LED irradiation, the photocatalysts exhibited efficient activity that increased from 29.1–267.9 μmol g−1s-1 upon increasing the TiO2 content from 2 to 5 % in the TiO2@HCSs, but a higher increase in TiO2 values led to a decrease in activity. This effect can be linked to the role of the carbon morphology on the reaction in terms of e- mobility from a VB to a CB in the catalyst.