Graphene-based nanostructures for enhanced photocatalytic degradation of industrial dyes

• Published in: Emergent materials (Online) Vol. 3; no. 2; pp. 169 - 180
• Main Authors: Ojha, Abhijeet, Thareja, Prachi
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.04.2020
• Subjects: Chemistry and Materials Science; Energy Materials; Materials Engineering; Materials Science; Original Article; Dyes; Band gap; Graphene; Photocatalysis
• ISSN: 2522-5731; 2522-574X
• DOI: 10.1007/s42247-020-00081-6

Graphene oxide (GO) is an sp 2 -bonded single atomic layer of carbon atoms with plenty of oxy-functional groups at its surface. The occurrence of large surface area (~ 2630 m 2 /g), surface functionalities, electronic, and mechanical properties make graphene-based compounds favorable for remediation applications. We report the synthesis and comparative dye degradation efficiencies of two titania (TiO 2 )-based composites, GO-TiO 2, and reduced GO-TiO 2 (rGO-TiO 2 ). Both the composites are characterized using SEM-EDX, TEM, FTIR, and XRD. We study the photocatalysis-mediated degradation of anionic dye Eosin Y and cationic dye Methylene blue (MB) in aqueous dispersions under white light and UV irradiation. Our results demonstrate that rGO(10 wt%)-TiO 2 composite shows the maximum degradation (~ 95%) of both 10 ppm Eosin Y and MB dyes in the aqueous dispersion. The enhanced photocatalytic activity of rGO-TiO 2 composites as compared to TiO 2 and GO-TiO 2 can be credited to the presence of efficient electron shuttling from the conduction band of TiO 2 into the conductive regions of graphene which eventually restricts further recombination of e − /h + pairs. Furthermore, the effects of solution pH and TiO 2 loading are studied on the degradation process.