Carbon/Graphene-Modified Titania with Enhanced Photocatalytic Activity under UV and Vis Irradiation

• Published in: Materials 2019-12, Vol.12 (24), p.4158
• Main Authors: Wang, Kunlei, Endo-Kimura, Maya, Belchi, Raphaëlle, Zhang, Dong, Habert, Aurelie, Bouclé, Johann, Ohtani, Bunsho, Kowalska, Ewa, Herlin-Boime, Nathalie
• Format: Article
• Language: English
• Subjects: Acetic acid; Carbon; Catalysts; Catalytic activity; Condensed Matter; Deactivation; Decomposition; Dehydrogenation; E coli; Engineering Sciences; Graphene; Hydrogen evolution; Hydroxyl groups; Irradiation; Lasers; Materials Science; Methanol; Micro and nanotechnologies; Microelectronics; Nanoparticles; Optics; Organic compounds; Oxidation; Photocatalysis; Physics; Polyvinyl alcohol; Radiation; Spectrum analysis; Synthesis; Titanium; Titanium dioxide; Ultrasonic imaging
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma12244158

Laser synthesis was used for one-step synthesis of titania/graphene composites (G-TiO (C)) from a suspension of 0.04 wt% commercial reduced graphene oxide (rGO) dispersed in liquid titanium tetraisopropoxide (TTIP). Reference titania sample (TiO (C)) was prepared by the same method without graphene addition. Both samples and commercial titania P25 were characterized by various methods and tested under UV/vis irradiation for oxidative decomposition of acetic acid and dehydrogenation of methanol (with and without Pt co-catalyst addition), and under vis irradiation for phenol degradation and inactivation of . It was found that both samples (TiO (C) and G-TiO (C)) contained carbon resulting from TTIP and C H (used as a synthesis sensitizer), which activated titania towards vis activity. The photocatalytic activity under UV/vis irradiation was like that by P25. The highest activity of TiO (C) sample for acetic acid oxidation was probably caused by its surface enrichment with hydroxyl groups. G-TiO (C) was the most active for methanol dehydrogenation in the absence of platinum (ca. five times higher activity than that by TiO (C) and P25), suggesting that graphene works as a co-catalyst for hydrogen evolution. High activity under both UV and vis irradiation for decomposition of organic compounds, hydrogen evolution and inactivation of bacteria suggests that laser synthesis allows preparation of cheap (carbon-modified) and efficient photocatalysts for broad environmental applications.